Portal Adventures.

The premise is simple; an Portal or wormhole appears! be it near caused randomly and unexplained, under the will of a powerful, random and bored diety or its artificial made and made by the main character via magic or science or found alien tech, etc. Doesn't matter, point is, it leads to someplace, somewhere within the world, the universe or multiverse and you are going to have fun with it by exploring the unknown or the known but in a new perspective.

Rules: Tiolet, or similar content are NOT permitted, other than that, have fun.