You can quest with Hydra and then if your opponent clears it with, say, a Maui - Hero to All, it not only banishes Maui but lets you deal 6 damage to something else on board
With only 1,008 Alpha copies printed, finding one in such high-grade condition is incredibly rare
Three is quite a lot just for card quality and won't bail you out of savage mana screws however it is typically played in more long term decks which are far less likely to keep land light hands
Its a similar thing to 0 toughness for an indestructible creature
Due to the long name, a casting cost couldnt fit on the card, so she comes with a one-mana cost of either black or red mana as long you have discarded a card this turn
Provided it lasts long enough, or you drop it late enough, it can seriously accelerate your game plan