Deltarune - Dark, Darker, yet Darker

It was Asriel's last day before he had to go to college, and Kris wanted to have one last adventure with him. So, Kris suggested they explore the strange mysterious bunker at the edge of town. However, when they go in, the both immediately pass out. When the wake up, they're in some strange, dark lab, where a strange, terrifying scientist lurks and gives Asriel a terrifying choice.