Plunge into Darkness 4/10 This is a Tutor to set you up or a mass sac outlet to try and close out the game
Many black-based decks can create a hefty amount of Treasure tokens, and just creating and sacrificing two Treasures deals 4 damage to everybody else
Channel and Sneak Attack don't have similar rules text, for example, but they overlap in their ability to do broken things with big colorless creatures, so you might pick up a Sneak Attack to support your early-pick Channel, and then prioritize the legendary Eldrazi creatures, Blightsteel Colossus, and Sundering Titan over a card like Karn Liberated, which only works with the Channel plan
With other Princess-specific cards like Wreck-It Ralph Admiral Underpants, Vanellope von Schweetz Sugar Rush Princess, Hans Noble Scoundrel, and Moana Of Motunui there is even more potential