Deal 7% more damage to low health champions. Gain AD/AP after kills or assists.
Summon Aery is fantastic lane dominance and annoyance rune on Teemo. With an Auto->[Q]->Auto you're able to double-proc Aery for really oppressive early game harass damage.
Tip: Make sure you're catching Aery as quickly as possible and abusing your early game pressure.
WhyThe Ultimate Hat
The Ultimate Hat allows you to further press your role as an "annoying little s***" by keeping tons of mushrooms up at all time all around the map and keep yourself safe from ganks in lane.
Celerity synergizes well with Teemo's [W], granting a bit of extra AP while your Movement Speed steroid is active.
The extra passive Movement Speed also help keep you sage anf allow you to abuse your lane pressure with repeated autos.
Scorch is the go-to lane harass/pressure rune and is a must have on Teemo if you're looking to get the most out of your laning phase.
Alacrity on Teemo is another great lane pressure rune as the extra Attack Speed will help you get more autos off for poison damage and Aery procs.
WhyCoup De Grace
Coup De Grace help you scale into the mid to late game. The extra bit of damage means if in unsuspecting enemy support accidentally walks into a mushroom when they are below 40% health they are likely to die.