Yes. The layer system dictates that power/toughness setting abilities will be applied before power/toughness modifying abilities.
They will become 0/2's with +X/+X.
November 15, 2014 9:34 p.m.
Due to the layers, the creatures would get the +x/+x added to the 0/2 but would lose the trample. Casting the sudden spoiling before the spell resolved, would of made a bunch of 0/2 creatures with trample since it checks the highest power on resolution.
November 15, 2014 9:38 p.m.
you should instead Sudden Spoiling in response to keep him from getting big fat guys