I feel like if you're going karn and newgin, you might as well just lean heavy into artifacts and basically just splash white, or go an entirely different route and go Izzet for Jhoira, The Antiquities War, Sai, Master Thopterist, counterspells, etc.
Pretty much. Instead of Zetalpa, primal dawn, you could run Karn, Scion of Urza and Ugin, the Ineffable to generate tokens to chip them down, or Gideon Blackblade to keep hitting them in the face.
Although, I will say, I was somewhat disappointed with Ugin, as his last incarnation was an absolute monster, with a useful + ability, a devastating AoE for a - ability, and a pretty gross ultimate: Ugin, the Spirit Dragon.
I can see a mono-white prison deck developing with the god pharoh's statue and The Immortal Sun with a strong artifact presence. Ravnica at War could be an extremely effective tool in this as well.
How even do you pull that off, though, ramping out to something like that in the first three or four turns? And you need to be able to reliably both have the ramp and the tax effects. I know I'm probably building a historic-good-stuff Thran Temporal Gateway deck of some kind, probably green and white for ramp, sustainability and enchantment removal (otherwise Ixalan's Binding? GG.) and probably Urza's Ruinous Blast but that's just fun jank, not really competitively viable.
and also painfully good in EDH
good this is uncommon or this would be another 10$+ card in no time
Although, I will say, I was somewhat disappointed with Ugin, as his last incarnation was an absolute monster, with a useful + ability, a devastating AoE for a - ability, and a pretty gross ultimate: Ugin, the Spirit Dragon.