Buff Carl only truly understands after the blast: infinite mana collapses spell cooldowns to almost nothing.
As additional notifications roil after the kill, Carl finally registers what never-ending mana actually means. His Heal spell's cooldown becomes almost nonexistent, and he starts casting it over and over while his body jigsaw-puzzles itself back together.
It is paired with his last five seconds of Immortality, and those two effects together are the only reason a man who detonated a bomb at his own feet is able to sit up, loot a corpse, and walk out.
The buff that turns Carl's healing into a continuous rebuild after self-detonation.