Flooding meets Fallen Elf... This card seems quite powerful, however I can't see any good use for it. It is a very poor lock: in addition of seven untouched creatures - same as flooding - your opponent has a chance to get powerful mutants, that will die only once in a while. On the other hand, if you want to fill your own side of the ground and hope for good mutations, since the first 7 creatures are untouched, you would need to fractal, which requires to splash in a third element. Graveyard will hardly work: if the abomination/mutant/death probabilities are the same as for Fallen Druid - this seems logical - there's only a 1 in 10 die chance.
All in all, this looks inferior to Inundation, which is already a bad card (happily it will get buffed by next upgrade, decreasing upkeep to 1
). One possible buff is to make it affect the whole board, at the cost of an increased upkeep and CC, but then it would definitely be OP.