RulingHall of Heroes (rules 1.0–1.4)
Black Panther: If an enemy initiates an attack against Black Panther but another hero or an ally defends against that…
Question
If an enemy initiates an attack against Black Panther but another hero or an ally defends against that attack, will Black Panther’s retaliate ability trigger?
[Second], if Black Panther defends against an attack, will his retaliate ability trigger?
Answer
No. Black Panther himself must be attacked for retaliate to trigger.
[Second], yes. As long as Black Panther himself is attacked, retaliate will trigger.
-Official FAQ (1.1)