Talk:Spell vamp/@comment-3529242-20111020033016/@comment-4068613-20111029172919

Jax's ult passive, while triggered on-hit, does not itself procure on-hit effects. You don't spell vamp from any of his basic attacks, but you do spell vamp every time you consume one of his stacks of buffs. His W merely empowers his basic attack, and doesn't really count as having done damage directly. So you get more physical damage out of his attack after empowering it, which benefits lifesteal, but even an empowered attack is still just an autoattack, and therefore triggers lifesteal isntead of spellvamp. Think about it this way: If an instance of damage can, theoretically, crit, it works off of lifesteal. Otherwise, it's spell vamp.

To further clarify, when you see the damage ticks from an empowered strike, it's only one chunk of health you removed. The damage from consuming a stack of Jax's Ult is dealt first as an autoattack, and then immediately afterwards as a mostly related effect. The first part, the actual autoattack, triggers lifesteal, but the magic damage dealt from his passive works off of spell vamp.

TL;DR W is on-hit, his ult passive is not. W empowers an auto-attack, while the ult deals damage independent from the auto-attack, although indirectly caused by it. W has no spell vamp, his ult passive does, but only from the bonus magic damage.