Three guardians watch over the pacifist timelines of the Alpha Timeline. When Chara escapes from a Genocide timeline and begins to wreck havoc in the Pacifist Timelines, it is up to the three to track him down and send him back to where he came from. This multiverse AU was created November 25th, 2016 by AGuardianOfDreams.
These three look after the Pacifist timelines and protect them from threats.
He lost everything because of Chara. What should have been a pacifist run was turned into a genocide run. He was saved from the killing blow at the last minute by Frisk and was reunited with Gaster in the White Void.
From a different pacifist timeline, Frisk is the sole survivor of her timeline thanks to Gaster, who managed to rescue here from the other's clutches. She is uneasy around Sans, though it's not fear; in Frisk's timeline she and Sans were a couple and had been dating. Her Sans had dusted in her arms while protecting her from Chara.
Lost long ago due to an accident, he is Sans' brother and has been watching over the pacifist timelines ever since he arrived in the White Void.
After being freed from a Genocide timeline, he sets about destroying Pacifist timelines.
An enigmatic individual, Aria claims to be chasing Chara through timelines to try and stop him. She teams up with the Sentinals to put a stop to Chara. She has a purple paint brush as her weapon and she is never seen on her own as she travels with the help of her companion, Inky.
An Ink Sans, unlike most versions he is has a gentle nature, is compassionate and is actually taller than most other versions, including the original Ink. He and Ink have actually very little in common aside from wanting to protect the AUs, have memory problems, and have the same type of magic. Inky is much more mature than Ink and while there's a lot he doesn't know about - or just plain forgets sometimes - he never wavers from his goal to help others.
- There is no actual "run" in Sentinaltale, due to the fact that it takes place in the White Void and Pacifist runs.
- Gaster disappeared when he fell into the CORE while on a routine check of the CORE with Sans.
- Sans, Gaster and Papyrus are all brothers, with Sans being the oldest.
- Sans was friends with Frisk before his timeline was destroyed.
- Chara takes over pacifist timelines by killing Frisk and due to not being human, absorbing their soul and essentially forcing a Reset; allowing them to go through the Underground to kill everyone. Because Chara is outside of his own timeline, he gains more and more EXP for each kill that he does, breaking, the usual limitation of LV 20. Having the red souls allows Chara to easily invoke a Reset if anything goes wrong, making him impossible to simply kill.
- Inky and Aria do not actually have a "universe" that they come from, both existing in the multiverse of Sentinaltale, but outside the worlds themselves.