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
This deck wants to ramp up quickly and use cards heavy end cards like OP08-069-charlotte-linlin, OP08-119-kaido-linlin, and OP01-094-kaido to carry the game.
There's a good reason for that popularity and since we're not on white, Damnation is simply put our best board wipe Cyclonic Rift is, according to EDH Rec, the second most played card in all EDH Decks posted online and for good reason, versatile instant speed board wipe (or as close as blue gets it), I can't think of a reason not to play it in any EDH deck running blue
For that, we dont have to go into the full mill suite that can put off people
Its free removal, it stops artifact and enchantment based combos when you have no mana open
Said yolky folks gave you a card when sacrificed, and given the success that egg decks had at the time egg became the MTG slang for sacrificial artifacts with a similar ability