There are: Partner Partner With Choose a Background Doctors Companion Friends Forever Partner / Partner With Partner first showed up in Commander 2016
Here you have a card that basically says Play another game of magic using the cards you have left
However, they also read, At the beginning of each combat, until end of turn, each other creature you control gets +1/+1 if it has flying, +1/+1 if it has first strike, and so on for double strike, deathtouch, haste, hexproof, indestructible, lifelink, menace, protection, reach, trample, vigilance, and partner. So were counting all of those in this little roundup, which puts them at the top of this list
Transform all creatures into food, then destroy them to power up your commander
Zero mana artifacts obviously have applications for many artifact-centric archetypes, but theres plenty more going on here as evidenced by the cards Constructed resum
Ill choose Whole New World for this example, as most matchups that will be the best play