This build is designed to not be that squishy teemo with the global taunt and actually be useful, too stick to enemy's do tonnes of damage and hopefully not get focused in team fights and Tank Shredding.

This build is a mixture of high damage and average sustain and the ability to assassinate the enemy's greatest threats.

the runes and masteries are designed too do as much damage as fast as possible early, to assist you in last hitting and harassing and allow you to set up for your later game.

During the Lane Phase focus on last hitting and harassing the enemy, my most used form of harass is auto attack blinding dart auto attack your auto attack speed should sync in well with your blinding darts travel time.

Upon Reaching level 6 plant your Noxius Trap in the brush leading down to mid lane too prevent you from getting jumped by the enemy lanes/junglers this will allow you to push with less chance of being punished for it.

Upon level 9 your toxic shot will be maxed and your damage should be exceptionally high especially against squishier opponents such as gang plank.

Mid and late game try and stay near your team while putting shroom in possible flank positions to ensure your team is safe and has map control, when ever your near dragon or Baron Nashor put a shroom at the entrance to make it so the enemy team can't kill them without your team knowing.

What To Do
In this order
Focus the ADC(Attack Damage Carry)
Focus the APC(Ability Power Carry)
Focus the Tanky Bruiser
Focus The Support
Focus The Tank
Always Stay back
What Not Too Do
Never be the first to go in always allow your team to initiate
Never focus the tank first
Never chase Through the enemy team to pick up a kill unless you are 100% Sure you can get it

Pros
Lots of hp
Lots of damage
Map control
Tank shredding ability
You don't get focused as much as all other Teemo's
Hard to get away from due to constant slows,
Cons
Can be shut down early
You may have a lot of HP but you don't have much armor or magic resist
%Health damaging champions such as Malzahar,Kog-Maw will often focus you
Early game is sometimes hard

Tips
1, If your losing your lane early don't push ask for help and last hit under the turret
2, If your getting focused really hard replace the Rabbidons Death Cap with a guardian angel
3, If Your Getting fed Really early you can replace the Frozen Mallet with a Trinity Force
4, your Shrooms are like wards shrooming the enemies neutral buffs not only helps but can also set you up for kills
Tricks
1, At Level 7 you should be able to hit a minion 2 times and the poison should kill that minion
2, If your engaged in a 1v1 with a melee champion plant a shroom behind you and tank there damage when you feel like your losing run backwards a bit 95% of the time they will follow and hit the shroom turning the battle to your favor
3, planting a shroom in the middle of a teamfight should make it explode and hit 3-5 people dealing alot of damage.

This Concludes my guide to Teemo
i hope to see you all on the fields of justice
if you made it to the end of this very long guide please leave a comment below
and if you ever see me in game say hi (IGN TeemoBro)
The End.