Rakdos Delirium relies heavily on graveyard-fueled value from Stitcher's Supplier, Nethergoyf, Street Wraith, and Detective's Phoenix's bestow-from-graveyard ability, so Rest in Peace is excellent, exiling their graveyard on entry and shutting off all of that recursion going forward. Obsidian Charmaw is a strong flying clock that dodges their removal-light, ground-based creature suite. Lightning Bolt is cut since it trades down against their efficient threats less well than Fatal Push, and Stubborn Denial is weak since this is a low-noncreature-spell aggro-midrange deck; Vexing Bauble adds another cheap disruptive piece against their free/cheap spells like Mishra's Bauble and Street Wraith's cycling. Watch out for their Thoughtseize taking key pieces before you can deploy them.