basically, this mod will add a Mimic Chest block to the creative Misc Tab, and a new mob, Mimic.
the block looks like a slightly larger chest (the actual chest has no inherent .json model, and I only know how to use MCreator) and when attacked or interacted with it spawns a mimic mob and removes the fake chest block.
the fake chest block can be crafted with a chest and an ender eye.
the mob looks similar to a creeper, and has 20 hp (10 hearts), and does 5 damage (2.5 hearts). it also drops a chest.
it is a simple proof of concept mod and until I (eventually) learn actual java coding i have no plans to update it.
However if anyone wants to make a better version, then, by all means go ahead! no credit needed, as I'm quite sure it's not an original idea.