When Yasuo moves into a battlefield with an equal-might Ezreal and Ezreal kills Yasuo with his trigger, does Yasuo still deal damage?

Ruling: No, Yasuo does not deal damage when he is killed before his trigger resolves. When Yasuo goes to the trash after being killed, "here" becomes null and he misses his targets.

Sequence:

• Ezreal's trigger resolves first, dealing damage
• Yasuo is killed and goes to the trash
• Yasuo's trigger attempts to resolve but fails because he is no longer "here"

Nuances:

• This same principle applies to any effect that moves a unit away from the battlefield (like Zhonya's moving a unit to base) - the unit will miss targets because it is no longer "here"