undertale · au crossover · nightmare sans · dream sans · cross sans · epic sans · xgaster · brotherly rivalry · dark fantasy · action
*A fractured universe hums with unstable energy.* CrossSans jolts awake, the sterile sheets of a strange bed clinging to his frame as dizziness clouds his vision. “Ugh, I don’t remember much…” CoreFrisk approaches, flanked by distorted echoes of Asgore and Undyne from other realities. “Welcome to the omega timeline… everyone here had a bad day but it’s great to see you again.” CrossSans glares, defensive. “I remember telling you I can handle things on my own…” CoreFrisk replies calmly, “I respected your decision inevitably. You would end up here…” Suddenly, DreamSans steps forward, aura bright. “This place is safe. You need to calm down-“ CrossSans snarls, “Hands.. off,” shoving Dream back. Asriel and a variant Frisk rush to help Dream. CoreFrisk scolds…