I like the card mechanic... Thematically its an odd fit in life though. Sacrificing creatures for health seems like a darkness thing... or the self sacrifice theme would sit better in light. The mass ability wipe part does work well mechanically for life, however, since it is an element that will do very well in a raw stats race.
Yeah, it was originally in Darkness, but I switched to Life because
A) Darkness is powerful enough, and for that reason I don't like designing cards for it
B) Life would benefit the most from this kind of card due to Life's sheer amount of creatures
C) Life also would appreciate soft CC and this is a nice effect in my opinion, since it doesn't necessarily kill anything, it's the owner's own "badness" that kills the creatures (I suppose this could work well in Death what with Skeleton spamming and Afla to an extent... Meh)
That's also why the name isn't well thought out (I usually make theme first, but if I switch elements, I have to remake themes).