Lige hvad jeg kunne finde:
Apparently a lot of people are having troubles with this one.. Not sure, but the trophy may be glitched or something, as others did mention they got the trophy even when using the concrete donkey and other weapons. I saw one guy say he got it by using the normal grenade only and without using the ninja rope or jet pack or anything else, not a single tool. you might want to try that if you used the Ninja Rope or Jet pack.
u cant suicide or get caught by mines when u launch STANDARD grenades.
I did it first time. Just hit one worm with a grenade, the rest can all teleport into the water or lava. That's how i got it, anyway!
TURN OFF MINES!!
Sorry for caps, just want to make it stand out nice and clear.
Håber det hjælper