Jugan the Rising Star

So happy I pulled it from the 400 MP pack.
Question though.
"When Jugan dies, +5/+5 to first creature. If there are 8 or more green gems, convert 16 gems."

So is the second ability triggered upon death or just anytime? I've not had it trigger tonight for anything yet. Also seems a waste to trigger upon death (99% likely on opponents turn).

Love,
Carl