Saundra, Realm Fabricator

+2: Create a 1/2 green Crystal Elf artifact creature token with "Sacrifice this creature: Add two colorless mana to your mana pool."
-3: Place a +1/+1 counter on each creature you control, then choose a creature type. Each creature you control becomes that creature type.
-12: For each non-planeswalker and non-token permanent you control, create a token that's a copy of that permanent.