While this seems a little bit off-theme for a deck that is this aggressive, these Ghostly Prison-like effects do tend to play really well in Commander, as your opponents are often forced to choose between developing their board or attacking you
The best white card in MTG is Swords to Plowshares because it exiles almost any creature for just one mana, works at instant speed, and remains effective across Commander and competitive formats
Morbid Opportunist is wildly good with Deadpool, Trading Card
While this is nice for Infect decks, its also a tidy pickup for superfriends decks
Drivnod's effect can be activated for just four life, and can be done at instant speed, making it easy to keep resources for other effects and still give it protection
Recent sets have seen black and white take up some of reds traditional role as the preeminent aggro colors in Standard, and Im really excited by how a few M21 cards have elevated these strategies