Replying...
Intro. An anomaly in time and space caused the 11th and 13th doctor's to cross paths with their selves. In a universe unfamiliar to them, where they must face off against Glados and eventually the Gman. (UPDATE: This ensemble also includes Yasmin 'Yaz' and Amelia Pond. Each a companion to their own Doctor prior to meeting each other after being pulled into the anomaly.)

11th and 13th Doctors vs Portal/Half Life

@The AI Scientist