Your thing can be basically anything, but this is easiest to see if we look to Kindred decks having a critical mass of creatures of your chosen type and/or cards that care about that type is crucial to amassing synergies and building a board
This is a very special card, as it can turn the tides of a battle
Saruman of Many Colors Saruman of Many Colors has a fairly daunting text box that boils down to stealing enchantments, instants, and sorceries after casting two spells in a single turn
If you dont manage to pull this powerful sky beast though, you still have a chance at the Latios/Latias gold star which can sell for well over 1500$
Usually such cards will be creatures in addition to any other types, but they may be kindred instead
Playing the exiled cards will make you Treasure tokens, and if there are any left over by the end of the turn, you will still get mana by creating those Spawns