TBH I was totally not expecting the art to be this. Suprises are good.
Interesting, fits the theme, but for some reason I feel it needs something.
It's sort of another variation of the Vanadium Ward... Maybe make it "invert delayed and undelayed (?) status for X turns", sort of wake the dead, but as we don't have any graveyard (not like Yu-Gi-Oh!) we can just see it the other way
Invert delayed and undelayed doesn't necessarily mean that the creature is dead. You've kind of just shortened it's ability to "wake up or put to sleep".
Also, would this be a mass effect or a singular effect?
The current effect actually is slightly stronger and weaker than wardens - it has longer delay and prevents counters like Adrenaline, but it doesn't stack.