WHAT THE HELL IS GOING ON?! [A Crossover Fic]

Suddenly, four figures jump out of the portal. The three adventurers shrieked and backed even farther from the portal. The four on the ground groaned in pain. One of the four, a dark-haired man wearing glasses and a hoodie embroidered with a red question mark, got up and held his head. "Holy hell, that hurt like a-" ...