Infinite ammo. Infinite zombies. Zombies that die with a single shot even if it’s a shoulder hit. Hotel corridors with magic smokeless fire that you cannot see through. There is not a single fire extinguisher in sight. And the fire is magically localized, does not spread, and is even present in the fire escape stairs where according to logic there shouldn’t be anything that can catch (or sustain) fire. You can’t climb over obstacles. You can only do baby jumps.
Nobody will call you out because your magic castle is made by the wrong type of bricks, but suddenly in a hotel you notice there are no fire extinguishers.