In order to prevent the opponent from becoming the monarch, Palace Jailer will exile one of their creatures, making it harder for them to take that title from you
Kefka, Dancing Mad Decks on EDHREC: 273 While a seven-mana commander is a pretty hard sell nowadays, especially in such not-rampy colors, Kefka is still a great commander option if you love stealing cards from other players
(They each put the top card of their library into their graveyard.) : Each player mills a card
While far from the most competitive deck archetype, Chaos decks can definitely spice up a Commander game and embrace the unpredictability of the multiplayer nature of the format
With 003-091-ursula-deceiver-of-all doubling songs and 002-089-prince-john-greediest-of-all really putting the hurt with every discard, Emerald Steel promises a lot of card advantage, especially with an unanswered 004-070-diablo-devoted-herald
Blue lacks the cheap rummaging, but it has looting spells as a way to keep pushing through