Andy has two morphs and a Grizzly Bears. The morphs are
Gift of Doom and
Deathmist Raptor.
Andy pays Gifts morph cost by sacrificing Raptor. When is the trigger event for “turn face up”? When it comes to casting spells it is specifically noted in the rules “here is where the trigger event is”, but I cannot find the corresponding for turning a creature face up.
I believe the ends result will be:
- Announce morphing up.
- Pay the cost, by sacrificing the Raptor
- Turn Gift of Doom Face up. Raptor Triggers.
- Attach Gift to Bears.
- Raptors ability is put on the stack.
The only support I find for this is however:
702.36e Any time you have priority, you may turn a face-down permanent you control with a morph ability face up. This is a special action; it doesn’t use the stack (see rule 116). To do this,
show all players what the permanent’s morph cost would be if it were face up, pay that cost, then turn the permanent face up.