Normally... He uses some slang (like "Heya") Talks a lot like Sans Talks with perfect grammar Uses common words mostly Uses contractions often When serious: Talks more like Chara If you made him mad, will usually refer to you as "kid" (He's technically 215 years old)
Example for normal: "Heya, pal! Long time no see. So, it's been a while. Did a lotta things while I was gone." Example for serious: "Do you know what would have happened if you had k!lled everyone? Well. Let us just say. You would not have lived much longer. I assure you that." Example for mad: "Look kid. You have nerve laughing at my height. Because you should know it is not my height that you should be afraid of. It is my strength. *Throws bully into nearest mountain*"
