it could have been the fire because sans takes the place of grillby, and sans has been shown in fanon to have a flaming eye, but it could also be lightning because i doubt you would make it fire cause thats too close to grillby, would want to make it slightly different, so i say B, but i could be wrong, im just making an educated guess

Description: full name: sans comic skeleton full pam name: john sans classic sprite sheet made by spectator/scott the watcher (thank you its so good) (some sprites were put together by me, like the fire engulfed sprites, but mostly all credit goes to scott.)