Gigatherium is expensive so that those weird Saproling decks don't attack for infinity until the turn
after they go off and cast Verdeloth with kicker. But you're probably right that it could cost less; at the very least, it shouldn't cost too much more than Keldon Warlord. How about 1GGG?
Come to think of it, I wasn't too sure of what detritus really meant myself, so here's what Webster's has to say:
de tri tus,
n. 1. rock in small particles or other material worn or broken away from a mass, as by the action of water or glacial ice. 2. any disintegrated material; debris.
Basically, it's a polysyllabic word for crud. Crud Sifter didn't seem to make a good name though.
And as far as its ability goes, I specifically made it that way so that the artifacts wouldn't be usable for the rest of the game. However, the ability is a little far reaching, so I'll change it to "Whenever an artifact is put into a graveyard,..."
Go read my list of white cards (if you haven't done so already).
