There are cheaper, easier ways of getting into Magic than Double Masters 2022, so we'd recommend holding off until something like Dominaria United comes out this September 9 if you want to get into MTG
You can use the gems to buy more packs or other rewards from the shop, or you can just go right back around and put it towards your next tournament entry
This five drop 5/5 on curve Naya colored dork gets bigger as more Auras are added in size, and that's card disadvantage if you kill it, but not without jumping through some targeted restrictions first, and you can Edict them, but they'll sac another dork, or Damnation the board, but respond with Heroic Intervention or just give it an indestructible Aura
I have a separate page documenting those on GitHub
Two instances of instant-speed flicker on one white instant is still a good deal