Sans was not as alone as he thought. the spirits of his friends had been following the child. As they arrived in the hall the last thing they expected was Sans. Undyne started shouting at him trying to get him to run, but he could not hear them. Toriel started crying and Papyrus, stood there. He was shocked. His brother was finally doing something, But it was not the safest thing.
"heya" they heard sans say.
"you've been busy, huh?... so, I've got a question for ya" Sans continued as he looked down.
"do you think even the worst person can change...? that everyone can be a good person, if they just try? heh heh heh heh..." Papyrus realized that Sans was saying what he himself had said earlier.
"all right. well, here's a better question." Sans looked up again, directly into Chara's eyes but he did something different this time. As he looked up his eyes were pitch black, all light and joy was gone. All three spirits shuddered even though they were already dead.
"Do you wanna have a bad time? cause if you take another step forward... you are REALLY not going to like what happens next." Sans threatened. As the child stepped forward, grinning like a maniac, Sans's shoulders slumped forward and he sighed and looked back down
"welp. sorry, old lady. this is why i never make promises." Toriel gasped as she remembered their promise and tried to say she forgave him but he could not hear her. Papyrus wanted to at least try to stop them but it was too late. The battle had started.
"it's a beautiful day outside." he said, standing there, almost waiting.
"birds are singing, flowers are blooming... on days like these, kids like you... SHOULD BE BURNING IN HELL..." No one had been ready for what happened next.
they watched Sans as he almost ripped his left hand out of his pocket, left eye socket blazing with blue and yellow magic, and flung it to the ground. They watched Chara's soul turn blue and slam to the ground, screaming as their body followed. They stood there shocked as Sans flung his hand back up and impaled their arm with sharp bones. As his smile widened when they screamed in agony while Karmic Retribution took effect they were feeling sick. They felt horrified as before Chara could recover Sans flung his arm out to the left and a barrage of bones impaled their screaming body to a column to the left. But what really shocked them was when Sans flung his hand up again, eye socket blazing with blue light as he summoned This... thing. The massive dragon skull stared at Chara's limp broken body and a high pitched whine was heard as it's maw was filled with light. Sans, still grinning, dropped his arm. They watched The Skull's jaw split in half as it's mouth opened to let out a powerful beam of pure magical energy. They all covered their eyes and when the light was gone so was the child and the column they were impaled on. The skull dissipated with a flash of light as Sans took his spot back in the middle of the room, seemingly waiting for something.
Undyne was the first to regain her senses.
"What. The hell. Was that?" she asked Papyrus. He did not know. None of them knew where it or this sudden burst of energy came from. They were left staring at Sans as he stood there. They did not know why he was waiting there but he was...