For example, you can't use Muldrotha to play a land if you don't have an available land play or to cast a planeswalker spell during your end step
Having a unique attack called Dragon Dance, which for the cost of 1-colorless boosts all of Haxorus attacks with 100 more damage, as long as the pokmon is in the active slot
You could look to this team up to cheat in massive legends, like Drakuseth, Maw of Flames, or keep things lean, focusing on cheap legends like Thalia, Guardian of Thraben that help you curve out and get haste quickly
You should carefully consider type synergy to avoid strategic weaknesses
A 5 mana buff my board then my board gets flying until end of turn feels like a tuned down Akromas Will
There will always be one player youre happy to give cards to, and a parlay at times is the only way to deal with an archenemy situation