You can choose a creature type with very few cards in Magic, such as atogs, rabbits, or raccoons, and fill out the deck with all colors of changeling cards since Morophon, the Boundless is a 5-color commander
The combination of coloured Mana used to pay to cast a Commander card dictates what colour of cards can be included in a Commander deck
The crux is deciding whether those other cards are worth playing on their own
Whether you're on the side of the wild dragons, the resolute clans, or both, Tarkir: Dragonstorm has plenty of cards for your decks
But it goes much further, and you can construct powerful pod lines with a little work
You can make an obscene amount of tokens with Adrix and Nev by combining it with just a few cards, like Helm of the Host for example