The mask has become very bored and as he comes across a house he gets some what drawn to it. The mask enters the house and starts terrorising the family. Unkonwing to him it is the Deetz family. The Maitlands have went to the afterlife so Lydia gets the ghost with the most to rid them of this thing.
Beelegeuse can get the maitlands if he is having trouble
The winner is decided by whoever drives the other out of the house for good.
Neither The Mask or Betelgeuse have any prep time. Betelgeuse has rushed in before even asking Lydia what exactly The Mask's powers are, and well The Mask has never seen Betelgeuse before.
The Mask
It's party time! P-A-R-T-whY? Because I gotta!
Vs
Beetlegeuse
Hey, these aren't my rules! Come to think of it, I don't have any rules!