Gapsule ( is a sub-boss in ガプセル Gapuseru ) ? Flying Battery Zone from the game , as well as its locked-on form, Sonic & Knuckles Sonic the Hedgehog 3 & Knuckles. The boss is modeled after a Capsule.
To defeat the boss, the player must stand on the button long enough to make the Gapsule to try crush him/her with one of his spike-ball arms. If the player jumps out of the way quickly enough, Gapsule will hit itself instead, dealing a hit in damage. After dealing itself six blows, the boss explodes, and the player proceeds to Act 2.
This was the final boss of the
Sonic & Knuckles game in the version of Sonic Jam for the Game.com. Like all other bosses, it has become much slower and less difficult to defeat.
Interestingly, There exists unused sprites for a boss enemy known as Janken Capsule in Studiopolis Zone's files. The boss has a very strong resemblance in design to the Gapsule and this boss would've utilized a Rock-Paper-Scissors gimmick for it's fight. Implying a possible callback to  Alex Kidd as well.
(29 August 2017). Retrieved on 31 August 2017. Sonic Mania: Hacking Diccussion
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