Undertale Battle Simulator 2 by bouncyyak - Game Jolt

Sans Simulator by G_Sluke32 - Game Jolt

UNDERTALE: ULTRA SANS FIGHT (UNOFFICIAL) by TheKiddo - Game Jolt

Dusttale Sans Fight by -TheKidd- - Game Jolt

3D Undertale! Yet Another Bad Time Simulator #1

Game jolt is the perfect place for undertale fangames : r/Undertale

Epic!Sans (GMS take) by annoying cat - Game Jolt

Dust Sans Fight Download - Colaboratory

Undertale Fight Simulator (Create Your Battle !) by NutelGame - Game Jolt

Sans' Real Special Attack (Custom Attack for Bad Time Simulator) by COOLSPAGHETTI - Game Jolt

Bad time simulator day seven! (Making it to the half-way point.) I actually managed to make it to his final attack twice! Link and description will be in comments! : r/Undertale