Ability triggers once per turn: draw a card and lose 1 life whenever cards leave your graveyard, promoting strategic graveyard management
This should not be confused, however, with combat as combat is a phase unto itself, where as fight is limited to dealing damage
Sacrificing creatures to it give it indestructibility which can help you keep your sacrifice outlets around after a board wipe
It has, in various forms, and basically all major formats (except for Vintage or at least, I havent been able to find any relevant, successful decklists), been a deck to consider, when packing your backpack to go to the local gamestore or bar to play some games
At the beginning of your upkeep, put all creature cards exiled with Gisa onto the battlefield under your control
So, if you transform a tapped creature, the resulting permanent will still be tapped