This is a vanilla hack where you play as a Monty Mole.
Almost no custom things were used.
-You can now carry items and punch nets.
-Removed time limit in "End of the hack".
-Removed the message boxes in "Generic Grassland" and "Morton's Castle".
-Changed the "presents" logo.
-Monty now turns red when collecting a fire flower.
This is definitely a hack. Levels are competently designed but not all that interesting.
My biggest issues are that Monty's hitbox seems to be a little taller than its graphics (you can see that Monty doesn't quite connect with hitting a block from below), and that there's no obvious visual different between regular and "big" Monty.