They can even be attacking players or planeswalkers that weren't being attacked
The Deck Minotaur Tribal Comparative Analysis 34 Lands 13 Ramp : Patchwork Banner, Arcane Signet, Sol Ring, Hazorets Monument, Neheb, Dreadhorde Champion, Didgeridoo, Neheb, the Eternal, Rakdos Signet, Firdoch Core, Ragemonger, J
The first choice for building a Commander deck is generally the commander, this is where your color identity comes from, and you add both partner commanders together to get the color identity
The rulebook included here is also a great resource, and is one of the clearest presentations of the rules I've ever seen
Soul Separator is an artifact that, for five generic mana, can exile target creature card from its controller's graveyard
This doesn't impact the sticker sheets they are allowed to use in the main game