20 card packs, 2 picks, 60 card decks

Any legendary creature, planeswalker, nephilim, or Earl of Squirrel can be your commander

Hybrid mana symbols count as either color, not both (Hogaak can be played in the 59 of any deck that is either green or black, but as commander he is still Golgari.)

Unexpected Potential and Worldknit allow you to play cards outside of your color identity.