I wanted to play that unfinished level Hidden Palace Zone in Sonic 2! It is a cut Level of Sonic 2 that can be accessed in level select of proto versions of the game. I had not played that before and so I really enjoyed it. I really loved Sonic 2 back in the day! It was fun to finally play a new level!!
I posted this video of Hidden Palace Zone in the Sonic 2 Prototype. I also found a couple versions of the level in Rom Hacks of Sonic 2. It's fun to play the stages and compare the videos.
This one is short because the level is unfinished and there is no end sign or boss
This next version of Hidden Palace Zone is from Sonic 2 - Lost Worlds Rom Hack. There are many levels that were cut from the game that were made playable in this rom hack. In this Hidden Palace Zone it is longer and there are 2 Acts
I like all the extra badniks and the underwater part
This last version of Hidden Palace Zone is from the Rom Hack Sonic 2 - The Secret Zones. I like this version of Hidden Palace allot. It is only one act with boss at the end. This Rom Hack is really good, there are many cool cut levels re-imagined for the game. Similar to The Lost Worlds. There are even more zones in this game
There is something about Hidden Palace Zone I really like! I was really glad to make this post. I like comparing alternate versions of different Sonic 2 levels that were cut from betas and put into a rom hack. Next I think I want to play all the different versions of Casino Night Zone! Another classic Level from Sonic 2!