Handplate Sans

1-S' personality is lazy, mischievous, apathetic and loves making puns even though it makes his brother mad but 1-S does it to playfully tease 2-P. He is smarter than 2-P, but he is physically much weaker and has less stamina. They are generally considered to be twins but as 1-S is more fragile, he may have been the first attempt. His pupils change color depending on his mood. If he is happy, they change into Green, if he is fearful, they change into Purple, and so on. However, he sometimes glows his blue eye. 1-S can heal, like 2-P, but is much less proficient at it than his brother. When he tries to heal Papyrus, he is never capable of doing it fully. 1-S is very attached to 2-P. 1-S' body appearance is a skeleton with black eye sockets and he wears a green hospital gown and a metal plate screwed into his right hand; it's signed '1-S'. The reason why he is left-handed is because looking at his right hand makes him think of being tortured by Gaster with his brother. Him and 2-P don't have real names so they just call each other "Brother"

2-P' personality remains mostly the same, staying merciful, optimistic and confident in both himself and others. He still has these traits, but they are pushed by Gaster, specifically his mercy. He always hopes Gaster will accept mercy. Just like Gaster and 1-S, his eyes glows depending on the mood, it can be purple when his fearful, it can be green if his happy and so on. 2-P has the appearance of a tall skeleton, black eye sockets, wearing a green hospital gown and a metal plate screwed into his hand; it's signed "2-P". 2-P is considered by Gaster to be less intelligent than 1-S, but 2-P has much more HP, is more physically resilient, and is stronger in magic than Sans. Papyrus believes Gaster can change his sadistic ways, though both Gaster and 1-S believe the opposite. 2-P suffers more experimentation than 1-S, and although 2-P is physically superior, it is because of this that Sans develops into an older brother figure for Papyrus despite that they are the same biological age.

1-S and 2-P speak in wingdings so gaster is the only one that can understand them