Talk:Teemo/@comment-114.77.203.242-20110630083448/@comment-189.27.230.202-20110630184245

It works with magic penetration, because it deals magic damage. That's why malady is such a good item on him. It doesn't benefit from spell vamp.

However, damage over time DOES proc spell vamp, but Teemo's toxic shot is an on-hit effect, not a skill like Malzahar's malefic vision or Singed's poison. Imagine toxic shot as a Bloodrazor, "every auto attack deals bonus magic damage". This "bonus magic damage" is not an ability, but an effect applied every attack, hence it does not proc SPELL vamp.