Gomazoa’s ability can be activated any time its controller has priority. It doesn’t need to be blocking any creatures.
01-10-2009
wotc
If Gomazoa isn’t blocking a creature at the time its ability resolves, only Gomazoa is put on top of its owner’s library, and only that player shuffles their library.
Random a card of Magic: The Gathering (MTG), but you can also roll the D20 dice, random a Planeswalker, have fun with the random rules and more.