Hellclaw Rager’s ability deals damage to an enemy. If they’re an elemental, it does triple damage. If the enemy dies, Hellclaw Rager is Enraged.
Hellclaw Rager’s second trait is Bloodlust: Become Enraged when an enemy dies.
So…
Whenever an enemy dies, Hellclaw Rager becomes Enraged (because of their trait). That would include if their ability kills an enemy. So why does their ability Enrage them? The only possible scenario where that would matter is if their trait is disabled (either it wasn’t unlocked, or it’s Arena, or they’re stunned).
Either way, that’s a really poor design choice. Either replace the Bloodlust trait, so the only way to become Enraged is killing an enemy with the Ability. Or replace the Enrage part of the Ability to something that actually does something, because they’re already becoming Enraged due to trait.