Extensive Teemo Guide - By Friend

Guide to Teemo
by Friend


~Index~


Intro... S1
Builds... S2
Tips & Tricks... S3a
The Art of Mushrooms... S3b
Playing Teemo... S4






~Intro (S1)~


This guide covers my favorite ways to build Teemo, techniques and strategies for his skills, and advice on how to synergize well with your team. Having strong core skills (map awareness, team communication, familiarity with strategies, micro, etc) is important to playing any character, but Teemo in particular benefits from it.


Section Summary:


S2 – Item, mastery, rune, and spell builds.
S3a – Useful techniques relating to Teemo's skills, and how to use mindgames to your advantage, as well as useful facts.
S3b – A section all about mushrooms and how to use them.
S4 – Suggestions on how to dominate lanes with Teemo, be a good team player, and similar.




~Builds (S2)~


There are a couple ways I like playing Teemo, but my favorite lately has been physical DPS Teemo. The thing to keep in mind with Teemo is that there are several quite viable ways to play him, and you want to choose the one that best suits your team. If you have good, strong carries played by players you can trust, you should specialize in map control and mushrooms; if you need DPS or carrying power, physical Teemo is a good choice, et cetera.


Always experiment with builds and strategies you find in guides if you think of something. It's a great way to find new stuff, and improve as a player.


Physical DPS


Focuses: Physical damage/Attack speed


A very powerful build for laning and teamfights, but your mushrooms suffer a lot for it. This is generally my preferred way of playing Teemo currently.


Skill Order:


Your passive poison (E) is important to level up early, and a few levels of Blinding Dart (Q) are vital. You want to get 1 level of Move Quick (W) at some point before level 10, but exactly where is up to you, and depends on how the game is going. If you find that you need to escape a lot (ew) or you're chasing down enemies frequently (yay) you'll probably want to get it sooner than later. I suggest it at 4 or 8 usually; you only need 1 level of it in most cases, so just get it when you need it and then max it out last.


1 – (E) Toxic Shot
2 – (Q) Blinding Dart
3 – (E) Toxic Shot
4 – (Q) Blinding Dart OR (W) Move Quick
5 – (E) Toxic Shot
6 – (R) Noxious Trap
7 – (E) Toxic Shot
8 – (Q) Blinding Dart OR (W) Move Quick
9 – (E) Toxic Shot
10 – (Q) Blinding Dart
11 – (R) Noxious Trap
12 – (Q) Blinding Dart OR (W) Move Quick
13 – other skill (probably Move Quick)
14 – other skill
15 – other skill
16 – (R) Noxious Trap
17 – (W) Move Quick
18 – (W) Move Quick


Items:


Berserker's Greaves (920g)
Last Whisper (1,965g)
Madred's Bloodrazor (3,800g)
Guinsoo's Rageblade (2,235g)
Guardian Angel (2,250g)
The Bloodthirster (3,200g) OR player's choice
Total: (13,470g)


If you're feeling squishy, get the Guardian Angel before the Rageblade. Games usually end by the time you're finishing your Guardian Angel in the listed build order; I like getting a Bloodthirster for the extra damage and lifesteal, but you might want to pick up something else if that doesn't seem useful. Doran's Shield is a really surprisingly solid starter item-- gives you a lot of survivability and makes it easier to survive ganks and dominate your lane until you sell it later.


I list the component items for each recipe in the order I suggest getting them, and each stage is for the next item in order.


Starting Items
Doran's Shield (435g)
Health Potion x1 (35g)


1st Stage
Boots of Speed (350g)
Dagger (420g)
Berserker's Greaves (150g)


2nd Stage
Recurve Bow (1,050g)
Long Sword (415g)
Last Whisper (500g)


3rd Stage
Cloth Armor (300g)
Long Sword (415g)
Madred's Razors (500g)


Pickaxe (975g)
Recurve Bow (1,050g)
Madred's Bloodrazors (775g)


4th Stage
Blasting Wand (860g)
Pickaxe (975g)
Guinsoo's Rageblade (400g)


5th Stage
Null-Magic Mantle (400g)
Chain Vest (700g)
Cloth Armor (300g)
Guardian Angel (850g)


After
-If you have lots of money at this point, buy green and red Elixirs while you're saving up for the next item
-Sell Doran's Shield for first component of next item
User's Choice




Masteries:




22/0/8 is a very solid build that helps Teemo's damage and staying power amazingly. Don't forget to switch out the point in Improved Exhaust with something else if you're not using that spell.


Suggested Runes:
+Armor Penetration (All red runes and quints)
+Attack Speed at 18 (9)
+Crit Damage at 18 (9)


Move speed quints are also pretty good. You can emphasize attack speed or crit damage if you like; I prefer a balance, but you might find your playstyle is different.


Summoner Spells:
*Exhaust/Teleport – My favorite combo. Great for 1v1s, teamfights, escaping, chasing, and freedom of movement.
Heal/Teleport – Particularly useful earlygame. Heal is handy for tricking people who think Teemo is weak, and for an extra bit of staying power you might otherwise be lacking.
Flash/Teleport – Can be useful for getting unexpected kills, and escaping situations that are going badly. Standard Flash usage, in other words.


* indicates my standard choice.


Map Control


Focuses: Mana/Cooldown Reduction/AP


Very fun way to play Teemo. Your mushrooms and poison do shittons of damage, and there is no better character or build to make the other team rage at you.


Skill Order:


You might notice that the skill order is the same as in the physical DPS build. It works very well with both styles of Teemo, and I've yet to find a reason to change it. Same notes apply, get Move Quick whenever you feel like you're starting to need more maneuverability. It's more useful to get it at level 4 than with a physical build, because you can start laying mushrooms more effectively with AP, though.


1 – (E) Toxic Shot
2 – (Q) Blinding Dart
3 – (E) Toxic Shot
4 – (Q) Blinding Dart OR (W) Move Quick
5 – (E) Toxic Shot
6 – (R) Noxious Trap
7 – (E) Toxic Shot
8 – (Q) Blinding Dart OR (W) Move Quick
9 – (E) Toxic Shot
10 – (Q) Blinding Dart
11 – (R) Noxious Trap
12 – (Q) Blinding Dart OR (W) Move Quick
13 – other skill (probably Move Quick)
14 – other skill
15 – other skill
16 – (R) Noxious Trap
17 – (W) Move Quick
18 – (W) Move Quick


Items:


Sorcerer's Shoes (925g)
Nashor's Tooth (2,645g)
Rod of Ages
Rylai's Scepter
Zhonya's Ring
Lich Bane
Total:


This certainly isn't the only way (or order) you can build an AP Teemo. It's my preferred way because it gives you early spammable mushrooms, better late-game viability thanks to RoA, slows to help your team from Rylai's, and pretty good AP and damage overall with Z-ring and Lich Bane. Note that I the Amplifying Tome I recommend you buy at the start is used for your Fiendish Codex, not your Sorcerer's Shoes. This is because basic boots + Move Quick is enough to keep you speeding around at this point, and the mana regen + cooldown reduction from Codex is very useful.


Starting Items
Amplifying Tome (435g)
Health Potion x1 (35g)


1st Stage
Boots of Speed (350g)
Meki Pendant (390g)
Fiendish Codex (420g)


2nd Stage
Amplifying Tome (435g)
Sorcerer's Shoes (140g)


3rd Stage
Dagger (420g)
Faerie Charm (180g)
Stinger (300g)
Nashor's Tooth (500g)


4th Stage
Ruby Crystal (475g)
Sapphire Crystal (400g)
Catalyst the Protector (450g)
Blasting Wand (860g)
Rod of Ages (850g)


5th Stage
Blasting Wand (860g)
Amplifying Tome (435g)
Giant's Belt (1,150g) – switch this with Blasting Wand if you're dying a lot
Rylai's Scepter (700g)


6th Stage
Blasting Wand (860g)
Blasting Wand (860g)
Sage's Ring (975g)
Zhonya's Ring (1,000g)


7th Stage
Amplifying Tome (435g)
Sapphire Crystal (400g)
Sheen (425g)


Blasting Wand (860g)
Null-Magic Mantle (400g)
Lich Bane (950g)


Masteries:




9/0/21 is my 'classic' mastery build for many champions, Teemo included. There are probably a few ways you might want to customize this, and I usually rotate a few slots (take out Good Hands, try Greed, get Improved Flash, get Presence of the Master, etc) depending on what I feel like trying. If you're using a build with Ignite, be sure to get the Improved Ignite spell in the Offense tree.


Suggested Runes:
+Cooldown Reduction (9)
+Mana at 18 (9)
+AP at 18 (9)
3 Quints in 1 of the 3 above


You might also want to try move speed quints.


Summoner Spells:
Heal/Teleport – Again, useful for tricking enemies when they're sure they have you. It's particularly useful on AP Teemo, I find, because it means you can kite enemies a little more dangerously-- run closer to them and get them to extend much farther then they would if they thought you had more HP, etc.
*Exhaust/Teleport – All sorts of fun things you can do, as usual. Mushrooms + Rylai's slow Blinding Dart + Exhaust while keeping up with Move Quick means you can do a surprising amount of slowing.
Ignite/Teleport – Recent strategy that popped up which looks interesting. Grabbing ignite and the Improved Ignite mastery lets you stack quite a lot of AP at level 1, and harass very effectively.
Clairvoyance/Teleport – For full map control. When someone trips your mushrooms, such as at dragon, you can drop a clairvoyance to see if they're luring you or actually doing something. Personally I don't use it very often, since I don't like losing out on effectiveness in fights, but it is viable.


* indicates my standard choice.


~Tips & Tricks (S3a)~


This section covers some useful stuff you can do with your various abilities, and things you can do to make your abilities help your team overall, as well as various factoids of information about Teemo that will help you improve your game. Mushrooms have their own section (S3b) which deals specifically with placing mushrooms effectively, but there are several tips that include mushrooms in the main section.


General


Playstyle Tip: Mindgames are a big part of playing Teemo, as you'll see throughout this and the next section. Learning how players of different levels (newbie, idiot pub, smart pub, high-level) react and plan in various situations means you can anticipate their actions, and counter them sometimes before they've even acted. Player psychology is very important; you will not regret making a study of it.


Map Control Tip: Keep track of your mushrooms. If the mushroom you had at dragon disappears, then alert your team as soon as you notice. Your team will usually notice if an enemy champion runs near or trips a mushroom, but it never hurts to ping the map as well. Mushrooms aren't things you fire and forget; they're active things you need to notice and tally as part of playing Teemo.


Blinding Dart


Strategy: Blinding Dart & Exhaust
This skill and summoner spell make an excellent pair. Combo'ing them has two primary uses:


In teamfights, you can lock down the primary carry first with one then the other to disable their damage output for a sizable chunk of the fight. Alternatively, if they have two high damage champions, you may cast Exhaust on one and Blinding Dart on the other simultaneously (or wherever is appropriate in the course of the fight, for example to save a dying teammate), and lock down two enemies at once.
In 1v1 fights, I like using Blinding Dart right away (so it's on cooldown and will be up while the fight is hopefully still going), and then letting the enemy hit me for a few seconds before I use Exhaust. The reasoning is pretty simple: letting them hit me a little lulls them into a false sense of security, and makes them greedier for the rest of the fight because I appear to be weaker. Slamming Exhaust on them when they think they're winning usually catches them quite off-guard, and sometimes makes them run just because you cast it. Try to use it when they're low enough you're pretty sure you can kill them by chasing them down, or when you're pretty sure that you're not going to win.


Ganking Tip: Blinding Dart does NOT apply your passive poison when it hits. If there's a case where you think your Blinding Dart will kill someone, try to auto-attack them once first to apply your poison and then Blinding Dart them. This usually means that your poison will finish them off even if your Dart couldn't.


Harassing Tip #1: Blinding Dart has great range, and is useful for harassing enemy champions. Be careful not to overdo it, though, and always try to save at least 150~ mana in reserve in case you're unexpectedly ganked, or have a chance to grab a kill that only your Dart will secure.


Harassing Tip #2: One of the other useful features of Blinding Dart is that it's pretty good at fucking up someone who's trying to last hit. Try and time your shot so that it'll prevent them from getting a creep kill they expect to get, and throw them off momentarily. By doing this, you might convince them that you'll keep doing it in the future, and make them play more defensively than they otherwise would.


Move Quick


Obvious Tip #1: If you're hit while Move Quick is activated, you get knocked out of it, and Move Quick goes on a 6 second cooldown. Don't activate it when you're attacking an enemy champion and there are enemy ranged creeps nearby, because they'll usually just knock you back out of it right away. The only case I've found where it's useful to activate it anyway is when the other champion is nearly dead, and I just need a 1 second burst of speed to get a last hit on them.


Obvious Tip #2: There's no downside to keeping Move Quick on as much of the time when you're running around the jungle as possible. Always keep an eye on the ability, and make sure you're not using efficiency by not using it when you could. Always activate it when you're fleeing from fights, leaving lanes, or were hit once and knocked out of it, but probably won't be hit again. The corollary to this is that you might want to not activate it right away when fleeing from multiple enemies if there's a chance one of them is going to use a long-range move that will hit you before you get too far away from them anyway. Save it for after it hits you, but be sure to use it then.


Toxic Shot


Warning: If you apply your poison on an enemy champion and get in range of their turret, it WILL aggro you first and foremost, because that counts as actively attacking the enemy champion. Avoid taking unnecessary hits because of this, and hold off harassing when you get near the enemy turret. Note, however, that you can use this to distract the tower while another ally is attacking the enemy champions if they're in greater danger than you are.


Other Warning: Toxic Shot has a nasty way of stealing neutral creeps from teammates who you're helping. Pull off earlier than you think you need to just to be on the safe side. Nothing more fun than explaining to a pissed off Ashe why you have her lizard buff as the first creep wave is spawning. =P


Technique: Poison Spreading
Attack each enemy creep in a wave once to apply your poison to each one, making the enemy wave weaker overall, provide less security for enemy champions, and easier to last hit for yourself and your teammates. Furthermore, poison spreading (or not) lets you control how hard the enemy is able to push; meaning you can set the ones in your lane up for a gank by holding back on your poison for a few waves. Be sure to do this to enemy champions too, when you're able. Snipe them with a poison shot here and there, and you'll notice that they'll quickly start playing more defensively, and give you greater dominance over your lane.


At high attack speeds, it's possible to apply your poison to an entire large creep wave in about 2 seconds, if you're quick about it. The only downside to this technique early on is that you're likely to lose a few last hits because you're busy keeping your poison applied. That's ok. Keeping the enemy pushed back often outweighs the drawbacks.


This trick is a very core element of playing Teemo, and is one of the reasons he can be such a powerful laner. That said, surprisingly few people take advantage of it at all, let alone consistently. Use it.


Kiting


Kiting & Harassing Tip: If an enemy champion is deadset on killing you and you're pretty close to your tower, you can usually turn around and auto-attack once to slap a poison on him while you're running. If you're able to pull this off a few times without taking damage, it's possible to around the gank and make them run. Don't get carried away; unless you're quite confident you can turn it into a kill, play defensively enough to escape.


Teamplay Tip: Remind your teammates that they mushrooms available to kite enemies through. It's no good to have them down if you're the only one utilizing them. Of course, be sure to actually have the mushrooms for them to kite over in the first place; more on that in S3b.


Move Quick Tip: As mentioned above, don't forget you have Move Quick available if you get knocked out of it from damage. You can turn this into a mindgame by leaving Move Quick off for a little while while you're being chased if you have help coming, because the chaser will usually be much greedier if he thinks he can run you down and catch you. The end result, if all goes well, is that they'll overextend more than they wanted to, and die in a countergank.


Ganking


Strategy: Initiating through Kiting
While you're not a very good initiator through traditional means (running in and blowing shit up with massive disable), you can be pretty effective at luring enemies back to your team by engaging solo and kiting them back, preferably through mushrooms. What it takes to get enemies to chase you varies depending on the player, and you can hopefully figure out the required amount of force by observing them throughout the game.


Teamplay Tip: Mushrooms and Teleport
If you have mushrooms positioned to allow backdooring or an effective gank, alert your teammates to that fact at an appropriate time (when you have enough up and with teleport to actually initiate the gank; when backdooring would be a good tactical move, etc). One of your jobs is to keep your team updated on what strategic possibilities they have available through your mushrooms, so be sure to be aware in this role.


Pushing & Defending


Strategy: Clearing Lanes
You have a couple means of clearing lanes quickly available to you by midgame. The effectiveness of each largely depends on your build: mushrooms boosted by high AP rape creeps and you can afford to place them more carelessly; and poison spreading works wonders when you have the high attack speed to make it work via a physical build.
First method is to drop a mushroom on the creep wave near the caster creeps, and make all the creeps continue aggroing you until the mushroom explodes. You then probably want to snipe the creeps that look like they won't die on their own, and move on.
With a physical build, you can efficiently attack each creep once and rotate through the wave until they're all dead. While it doesn't sound as fast as focusing one creep at a time, your poison in conjunction with your high damage make it faster than the alternative when facing large numbers of creeps.


Strategy: Mushroom Tanking
While situational, it's useful to know that turrets prioritize hitting mushrooms before creeps and non-aggressive (not attacking enemy champions) champions. Because of this, you can drop a mushroom within tower range, and the tower will focus it and save you a hit.


Tip: Prioritizing Creeps
When clearing large waves of creeps, spread your poison on caster creeps first, melee creeps second, and cannon creeps third. If you have armor penetration runes, focus cannon creeps down after poison spreading first, because you can shred through their armor most effectively.


Note: Farming with Mushrooms
Creeps that die to your mushrooms give you gold wherever you are on the map. Dropping a mushroom before you leave a lane where creeps walk can net you some extra gold and slow down possible pushes from the other team.


Teamfights


Teamplay Tip: Picking Targets
Effectively choosing targets in a fight is affected by a few factors. One, you should always try to focus-fire the same targets as your team as a general rule. Two, if your team is obviously focusing the wrong target (let's all chase Alistar lololol), then switch to a more appropriate target and try to get your team to follow your lead. Three, if something comes up in the fight that puts your teammate in mortal danger, you should do what you can to save them; but only if doing so does not prevent you from getting more kills than the number of deaths you would prevent.


As far as actually picking and prioritizing targets, you should follow a general order:
I. Carries and the squishiest champions first.
II. Support champions.
III. Tanks and anyone else.


Of course, you are not limited to using Blinding Dart on your primary target; if there's a physical carry your team can't focus for whatever reason, throw an Exhaust or Blinding Dart on them in addition to auto-attacking your team's target. This is usually more beneficial than using it to damage the primary target.


Teamplay Tip: Saving Allies
As Teemo, you have available to you several ways to possibly take focus off an ally, and save them from what seems certain death. Having a trail of mushrooms available for your ally to run through is one, of course, and is covered in greater detail in S3b; in most cases you'll want to employ a bit of psychology and focus-firing to save the day instead.
One approach is simply to start focusing whoever is attacking your vulnerable ally. If you deal sufficient damage at that point in the game, as well as having blind and possibly Exhaust available, you can delay your targeted enemy long enough and deal enough damage to make them strongly reconsider attacking that particular ally. I find especially if you have outrageously high attack speed (in the area of 2+ attacks per second), the visible effect of a player seeing their champion being hit that many times is scarier than the actual damage being dealt. Use that to your advantage, and see if you can scare them away.
Mushrooms are also useful. Try and use Move Quick to get ahead of them (assuming you're not being attacked yourself), and lay a mushroom where your ally is going to run. If the teamfight is relatively stationary, then drop a mushroom nearby, but a little in the direction your team would want to run if they'd retreat. Thus if the enemies become more aggressive and move in that direction, they'll probably hit your mushroom, and be tidily slowed and damaged.
An additional fun trick with mushrooms is if your ally has some form of semi-invulnerability (Judicator's ult, Tryndamere's ult, or what have you), is standing in exactly the same place, and the attacking enemy just keeps attacking and tries to wait it out. Drop a mushroom practically on top of him, and it's likely that it'll trigger before he tries to move out of range.


Teamplay Tip: Chasing
There's frankly only so much you can do to herd a running enemy in one direction or another towards your mushrooms. The best you can do is with Rylai's Scepter or Exhaust to slow them, and run near them and to the side-- staying, of course, on the side you don't want them to run, and hope they don't try to go past you, particularly if it means staying in range of you longer. Nonetheless, Teemo is a good chaser because of Move Quick and his poisons, so you should usually try to focus on killing the target if herding them doesn't look like it's going to work.


Neutrals


Tip: When to take buffs
Physical Teemo is a very good candidate for lizard and golem buff, and AP Teemo is also a very good candidate for golem buff, and occasionally lizard as well.
As a physical Teemo, the only times when you want to not ask for the buffs are when one or more of your allies are jungling and need them, when a particular lane aside from yours is going to be pushed extra-hard (by a solo in the earlygame, for example), or when another champion on your team has a specific use for one of the buffs (Taric getting golem buff to feed his ult, for example).


As an AP Teemo, you don't really need golem buff until you're level 6 and can start laying mushrooms, at which point you usually have the highest priority on it. Lizard buff can be very useful for harassing your lane at the start if no one else needs it, so don't be afraid to ask for it.


Tip: When to take neutral creep camps
Since Teemo can farm lanes moderately well, it's usually better to leave the creep camps in your jungle to allies who need it more. In the enemy jungle, it's not a bad idea to steal a creep camp while you're waiting for the cooldown on your mushroom to refresh, assuming of course it's safe to be there for that long. In short, Teemo is good at taking creep camps quickly, but he can farm well enough that he doesn't need them to excel.


Tip: When to dragon
Whenever you're strong enough and aren't needed elsewhere. Physical Teemo can solo dragon pretty easily, albeit a little slowly, with only a few items, but AP Teemo has a harder time of it. Use judgment based on how many enemies are missing, how hard lanes need to be pushed, what the rest of your team is doing, and similar factors.




~The Art of Mushrooms (S3b)~


Ah, mushrooms. They're what make Teemo be Teemo, no question about it. When placing mushrooms, there are several things of which you should be aware.
Players: Watch how the enemy players move, how they plan, how they think, how they attack, how they chase, how they run; all the little details. Those details are what let you place mushrooms in exactly the right places to trap them.
Types: I mentally divide mushrooms into several categories when I'm playing Teemo: scouting mushrooms, attack mushrooms, and defensive mushrooms. If the other team is moving about the jungle with great coordination, I want to focus on scouting mushrooms to function like wards; if they're pushing hard then I'll drop mushrooms in lanes to slow down pushes; and if my team is doing a lot of kiting and running, I'll place mushrooms at bottlenecks in the forest to try and ensure as many escape routes as possible.
Gameflow: Sometimes there are locations in a game where putting mushrooms just isn't useful. Even if you're getting out a ton of mushrooms but not many of them are being hit, you likely want to reassess your placements. On the other side of the coin, if your mushrooms are being tripped almost as soon as you put them up, you might want to place them more defensively so that you'll have mushrooms on the map in reserve.


Key Locations
There are a few places on the map where it is absolutely vital to have a mushroom as a ward.
Dragon camp: placing a mushroom either in the brush right outside the dragon's camp, or nearly on top of the dragon itself is one of the first locations you should secure with a mushroom after you hit level 6. Don't get lazy about putting them there, either-- if they drop or expire on their own, it doesn't hurt to leave one there in case the other team tries something surprising.
Baron Nashor: same as above, except it's not important to have a mushroom there before the 15-20 minute mark. After that, it's necessary.
Ends of the river: there are four places you want to try and keep mushrooms active in the river. At either end of the river, right outside the lanes, and in the two patches of brush by the middle lane.


Scouting Mushrooms
These are defined as mushrooms placed to keep an eye on a location, and warn of enemies doing things; they can also double as defensive mushrooms. In addition to the locations mentioned above, there are a few handy places you'll want to drop mushrooms if there's a lot of movement in the jungle.
Rune creeps: place mushrooms near the golem and lizard buff creeps, particularly if anyone on either side is jungling.
River exits: wherever the river exits into the jungle is not only a good bottleneck location to put a mushroom, but it warns of impending ganks and enemy movement as well.
Side lane brush: drop one somewhere in each patch of brush. This becomes less important as the game goes on and champions stay in their lanes less and less.


Attack Mushrooms
This type of mushroom is designed to be tripped either pretty soon after it's placed, or when something specific an enemy does should trigger it.
Creep-killers: place these right where the creeps walk, but far enough back from any oncoming wave that the mushroom has time to fade from view before the creeps get there.
Lane controllers: place these near where creeps walk but not on where creeps walk. These prevent your opponents from being too mobile, lest they trip mushrooms. These also can stop ganks on your lane if you place the mushrooms in such a way the the would-be gankers have to chase you over them, or trip them as they're coming towards you.
Midfight traps: If you think a fight is going to occur near you on the map, or you're planning on initiating one, then drop a mushroom nearby in a place that it's likely enemy champions would trod on them. The purpose of these is to soften enemies when they come in, and to slow them when they're chasing or running.


Defensive Mushrooms
Probably the most useful overall to your team, these mushrooms are ones placed in bottlenecks and other locations that are easy to run to in order to escape enemy champions, or lure them into a vulnerable place.
Any bottleneck on the map is a good candidate. The more traffic it sees, the more you should consider it as a routine place to put mushrooms. Generally the exits and entrances to the jungle and river, clumps of brush, and paths going to and leading from the lanes are likely spots.


Placing Mushrooms Just So
The fine detail of where *exactly* you lay a mushroom in any given location is a big part of how effective they end up being. As an example, mushrooms placed in exactly the middle of bottlenecks probably won't be hit as often as mushrooms that are placed slightly to one side. Players who are running or chasing and trying to be efficient in their movement are likely going to want to cut corners, and won't hit the bottleneck at exactly the middle, meaning there's a fair chance your mushroom would otherwise miss. So, a few tips:
Angle your mushrooms. Like I just said above, put your mushrooms offset from the center of a spot to a place where champions who are running tight corners are likely to go.
Switch it up. Don't ever put a mushroom in exactly the same place twice. You can (and should!) put many in the same general locations, but you should always place them a little bit off so players who try to guess ahead and avoid the spots where you previously placed them will instead run into them in their new locations.
Read the players. Get an idea of the style of players you're facing, and place mushrooms accordingly. If they like using certain lanes in the jungle, trap those up and force them to make new plans or just take the mushroom hits.
Don't be afraid to experiment a bit. Try putting your mushrooms in somewhat odd locations, and see what happens. As an example of how this can help, I figured out that it's a good idea to put a mushroom between the two patches of brush in a side-lane. Why? Because almost no one expects a mushroom to actually be there. Everyone thinks that the mushrooms are going to be in the patches of brush themselves, so they tread carefully there and then run right to the other patch, hitting the mushroom on the way. That is helpful in escaping ganks, because most gankers don't think to avoid that bare patch.


A lot of placing mushrooms comes from experience. The more you play Teemo, the more you figure out what works and what doesn't, and which common paths people take. So don't worry if you feel insecure about your choosing spots in that regard; you're likely to figure it out rather quickly with practice.




~Playing Teemo (S4)~


After grabbing your items and determining your lanes, you'll probably stay near your tower until the creeps arrive, unless your lanemate (if you have one) is a good ganker, in which case you should try for first blood from the brush. Laning with Teemo is pretty easy once you get the hang of it, and allows for some very hard pushing.


Solo vs. Duo
One of the first things to consider is how you want to set up a lane. Contrary to what some believe, Teemo is actually quite good in a duo lane. Poison lets him keep the enemies harassed and the creeps weakened, and his lanemate can easily farm, push, and help harass in most lanes. Further, a lane where one or more people have Exhaust can usually guarantee a first blood thanks to Toxic Shot.
Duo Pros
-Very powerful lane presence
-High chance of a first blood, and other early kills
-Decent farming potential
Duo Cons
-Takes longer to get mushrooms
-Might not get an easily harassable matchup


Solo lanes are good for Teemo as well, however. It almost guarantees faster access to mushrooms, and Teemo can hold his own very well in most lane setups. His bane is tower-diving enemies in the earlygame, because he's unable to do much against them, he has relatively low HP, and fleeing from the tower with a ganker in tow is almost certain death.
Solo Pros
-Quick access to mushrooms
-Still good lane presence and harassing
-Can usually hold off even a duo lane
Solo Cons
-When you're ganked, you're pretty fucked
-If you lose control even briefly (random early death, for example), it hurts your lane dominance pretty hard


Harassing
Your role early on is to utilize poison-spreading a great deal, harass enemy champions by darting in and out of combat, and using your long attack range to your advantage. You can play aggressively, as long as you stay out of reach of the other champions. Being disabled is very bad for Teemo, and usually leads to his death.


Preventing enemies from last-hitting is made easy by staying near your caster creeps, and attacking them once when they get near your melee creeps. No one likes Teemo's poison, and almost everyone falls back after getting hit with it a few times. Stay in position near your creeps even after they fall back; there's a pretty good chance they'll try again a few times right after they're hit, and if you poison them again it makes them play quite defensively for a few minutes thereafter.


Other Champions and You
Always try and play off the strengths of your allies. If your lanemate has a heal, play more aggressively than you normally would, and your farming and harassing will improve from it. As far as playing versus certain types of champions, keep some things in mind:
Disables are very, very hard on Teemo. Your long range lets you harass pretty well even by staying near the back, and you will want to take advantage of that when fighting champions who can stun you.
Tanks and melee champions are some of the easiest to play against. Harass them hard and often, and once they fall back you can push much harder than they. Be wary of them, but tank lanes are pretty easy overall for Teemo.
Casters are tricky. They can kill you easily if you're not careful, and you should treat any lanes including casters with plenty of caution.
Healers are annoying, but not overly hard to deal with unless their lanemate has a lot of lane presence. You always want to be in control of a situation, and healers can make it hard to manipulate an encounter to your advantage. Luckily, your poison and harassing abilities are effective at making them use lots of mana.
In lanes versus a duo, there are two approaches to take. Either focus your harassing on both equally (if they're both easy to harass and not playing very aggressively), or focus completely on one champion (if they don't have regen and the other does, or one is otherwise easy to lock down), and lock them out of the laning game. Both can be effective, and you should use your judgment to determine which is appropriate.


Getting Mobile in Midgame
Once you hit level 6 and get mushrooms, you should start moving around the map and placing them. Don't go too far at first; just trap the area around your lane, and work from there as you're able to leave your lane more and more. At this point you can also start helping with ganks more usefully, and you should utilize Teleport to assist other lanes that need your help; ganking, pushing, or otherwise.


Keep an eye on neutral camps, dragon, and maybe even Baron at this point. Strong early game control of neutrals leads to a better farmed and dominating team overall. If someone on their team is jungling, you can also lead an ally or two to attempt to gank them, and then mushroom up the area so they're wary to try again.


In general, you want to stay in lanes long enough to farm a little bit, and then keep moving to lay mushrooms where they're most needed, and help your team in pushes.


Teamplay
Playing with your team is pretty straightforward, and there are only a few points that should be emphasized.
Try not to lead the way. This might seem counterintuitive, given your passive and Move Quick, but enemy teams have a nasty way of focusing on Teemo first because he looks so squishy. Your best damage is dealt by staying in the back and getting a steady line of fire going, so try not to get in the way too much at first.
Stay aware even in teamfights about what's happening with mushrooms. It's entirely possible their reinforcements will trip a few on the way in.
To complement the above point, keep laying mushrooms even as you're fighting, chasing, and running. It only takes a moment, and one mushroom can change the course of a fight or chase when placed just so.


Lategame
You're a very good pusher at this point. Teleport to mushrooms placed far in their jungle, or to your pushing creep waves, and devastate things as far as you can comfortably go. Teemo does excellent damage against towers, and you should be able to do a good amount of damage even in short pushes.


Your mushrooms are still important, but a little less so than in early and mid game. Keep mushrooms up in important tactical locations (Baron!), and litter them over choice escape routes. Support your team in pushes and fights with the techniques and tips covered above, and you should do well.


~Closing~


Well, congratulations if you actually read through all of that. =p I hope there's some useful information to be found in there for everyone; things for experienced and new Teemo players alike. Teemo is one of my favorite champions not only because he's fun and versatile, but because he looks a bit like a flamboyant miniature elephant hunter, and what more do you need than that?


Thanks for reading, and happy mushrooming.