sorry, i did some research, and its called a "Alternate Universe" AKA. AU. sugary spire is a Swap AU. its something that you play as the main bad guy and the bad guy is the player you play as in the original game. a AU is like changed sprites, custom levels. hub world, enemies and ETC all combined together.
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duuude shudup, it's just an AU, i havent heard so much bullcrappery over Sugary Spire or Taco Tower. you guys just want to speak crap over silly little fangames. and about that statement of not copy-pasting, dude, 70% of undertale AUs are copypastas with characters slapped on top, with no differences on their personalities and such. plus minor spelling mistake, least*