Sandopolis Zone
From Sonic Retro
Sandopolis Zone, Act 1, as Sonic.
The third zone in Sonic & Knuckles and separated into two parts, Sandopolis Zone has a nice sandy desert for act one, leading to a giant, labyrinth type pyramid level for act two.
Sandopolis Zone's boss for act one can be defeated by continuing to hit it back toward the sand, or to jump in the sand until it follows you in
Sandopolis Zone's second boss can be defeated by getting on the first hand when it's out and then jumping up and getting rid of the sand defense around Dr. Eggman. Once away, you can attack his machine. Just watch out for the pokey hands and lasers!