Another World: Other Worldly Adventures

It was supposed to be a normal day for a student and his classmates. Now it has turned to a videogame come to life. They now have to go through other universes to go back to their own universe. Who caused this, an multiversal-entity that wants them to go wild on the universes they enter. Multi-crossover

note: I'm new to writing so critcism and advice would be appreciated