With Disney Lorcanas fourth set, Ursulas Return, focusing on the battle against a resurgent Sea Witch, the Enchanted cards took on a darker overall aesthetic
I find myself committing Rakdos slots to support for Sacrifice archetypes more often than not, and once you do that there are a lot of great Rakdos cards that are specific to that archetype
Being able to be such a disruptive one-unit army that forces opponents to interact with you on a different axis is fairly difficult, and there are a handful of games where Karn helps you interact with your opponent in exactly the right way by grabbing the artifact best-suited for the situation
It grants double strike on your exalted triggers, and can flashback cheap spells for free
Although the relatively recent Modern Horizons did have some shroud cards, they havent seen competitive play
A mono-blue control deck wouldnt be complete without some token dorks