Volcanic Island ($862) One of the top duals on our list, Volcanic Island (or Volc) is not only used in most of the top decks in Legacy/Vintage, but its also in popular colors for Commander
Koma, Cosmos Serpent ($8) Again, this is a mythic so its got that many less copies out there, but this is a card that MIGHT be a singleton as a finisher in some Simic deck and thats about it
Open booster packs to get this one
Still, Anowon would be a great addition to a vampire/rogue tribal build
In it, each player can attack each other player with their spells and creatures, like standard multiplayer games
If you're willing to spend a little, the Premium Pass and Poke Gold bundle can give you a big boost in EXP