Before going down the rules rabbit hole, let's look at an example to bring this concept to life
Kess, Dissident MageKess, Dissident Mage - 31,077 decks, 7,531 as commander Sauron and Bolas may have sunk their claws, teeth, and spiky armor plating into this list, but none of that was enough to dislodge Kess, the Snapcaster MageSnapcaster Mage-iest commander, from the top spot on this Grixis list
Ghostly Dancers and Gremlin Tamer are a great way to stock up on disposable creatures to use in combat, while Victor, Valgavoth's Seneschal can reward you for dumping all your mana into playing and unlocking many rooms per turn
I try to keep these Standard-legal and use these to teach the next generation of Magic players in my LGS every last Friday of the month