Sothera, the Supervoid (Mythic) Not an artifact, but an absolute powerhouse in control strategies
7 Hour Of Promise Promises Of Lands And Zombies You really want your ramp spells to come down in the early stages of the game, or provide extra utility if they're more expensive
Ninjutsu is an inherently complicated mechanic compared to something like first strike or deathtouch and is generally difficult to explain
There will be moments when you are exhausted, with nothing left to give
Even a light splash will also hurt your mana base, especially if you include the new tri-cycle lands, which are counterintuitively poor here
Perhaps this might be a good reason to bring them back so you can dish out heavier damage to your opponents, though you risk it getting stuck in your hand as a meager Shock as well