Fortunately, there are a lot of cards that do both of these things, since the deck naturally wants some number of sideboard cards that are multicolored anyway
Sinuous Villain: Menace is great for multiplayer
I also love this with two partner Commanders since that will be a fast kill
with no need to suffer through putting physical damage counters on Pokmon, no chance of giving your hand away by accident and not having to touch dirty cards in terrible physical condition, the GBC game already offers significant advantages over the real life version
I think they look pretty fantastic and much more vibrant than the standard versions
Chaos: Whenever you roll Chaos, put a Legendary artifact equipment named The Ashbringer with Equipped creature gets +5/+5 and has First Strike and Vigilance, Equip 3, and Sacrifice this permanent when a player planeswalks