If Kothophed dies while enchanted by an opponent’s aura, it won’t trigger for the aura.

When a creature dies while it has an aura attached to it, the auras don't technically move to the graveyard with the creature. They wait until they're on the battlefield unattached to be put in the graveyard, immediately AFTER the creature dies. This is rarely relevant, but today you can learn when it matters!

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