Arcane comet; Teemo's orbital Strike.
Soo, let me start off by saying, i like arcane comet. its a nice little bit of dmg to reward someone for skillshots. (mostly)
Now, let me say that i think arcane comet should not be a global skill. people like teemo, gangplank, etc, should not be rewarded with free damage from something that is pretty much already a free-damage skill.
I think arcane comet should have a limited range. Not totally insanely small.. but something, atleast.