I love undertale and undertale fan-games :)
[Lovecraftian Killer!Sans] - 'Under the Tale of Sleep' Full Cast P1
[Underfell] - Papyrus Royal Armour
[Underfell] - Gaster
Dusttale AU challenge, but the main concept is phantom Papyrus.
Dusttale AU challenge, but SP! Dusttale
