The Nightmare looks great at reanimating mid-sized creatures and it can feel like an engine just like Recurring Nightmare can, especially if youre trying to bring back creatures with powerful ETB abilities, like Grief
If the player doesn't, creatures they control can't attack you this turn
Bursty draw and repeatable draw is big in Commander these days, and going over seven cards in hand is easy
I think Richard Garfield wrote that as the Twelfth Commandment of Card Design
Kenrith's ability to pull creatures back from the graveyard could help with this, though I don't know how often I'll really want to use Kenrith to saddle up The Gitrog, Ravenous Ride
While building a chaos deck could be a fun and rewarding experience, its maybe one best taken alongside friends