All in all, I think making cards as available as possible is only a good thing especially since the collectible aspect of MTG will not be going anywhere anytime soon
It makes it less about the strongest cards and more about how valuable a card is
Black A Tonberry stabbing from the dark, or an evil paladin hell-bent on destroying the world, the villains of Final Fantasy are often more famous than the heroes
However, effects that stop a creature from untapping "during your untap step" or "during its controller's untap step" won't stop that creature from untapping during another player's untap step, and as such, Prop Room's ability will cause that creature to untap
It appears to be identical to morph except that the creature has an additional ward 2 while its face-down
I would suggest however using this card early in the game and putting two energy cards on it and then keeping it in the active Pokemon spot as long as possible and while you're doing this I would get a Pokemon on your bench that you want to use and start putting energy on it, then you can use Golduck's Water Slide move and move those two energy cards to your benched Pokemon after doing the damage and the next turn retreat Golduck out for free and move in that Pokemon you transferred those energy cards to
