White and blue, not so much
The floor on these in a deck triggering multiple upkeeps is still very high, especially when youre playing one, become the monarch, and then get your combat damage trigger from Obeka
The reason for this is mainly that since the printing of Ragavan, Nimble Pilferer, Dragons Rage Channeler and Murktide Regent the tempo archetype reinvented itself in being primarily blue-red and making Deaths Shadow not a necessary creature for tempo shells anymore
It has ten distinct color pairs, each with its own themea step away from Core Set 2020s mostly loose tricolor themes
A cheaper but a bit less good Chaos Warp
He does sit high on the curve for Artifact decks, but the potential to keep fueling the fire may be worth finding a spot for him