When that happens, you get to put a +1/+1 counter on it
Garuda is fought starting at level 44, with players limited to level 46 abilities, though there is also a Hardmode fight available at level 50 with a different strategy
Both are good, but Essence Flux has the benefit of making things slightly stronger
as long as you had answers to the cards you let them keep on top of their library
Does your meta have decks that use Urborg, Tomb of YawgmothUrborg, Tomb of Yawgmoth, Cabal CoffersCabal Coffers, or Nykthos, Shrine to NyxNykthos, Shrine to Nyx as part of their win condition
Part of the reason why I can recommend Legacy at all to people who dont have infinite money is that you can generally sell your deck for more or less what you put into it and sometimes quite a bit more