Marvel Universe

The Marvel Universe refers primarily to Earth-616, the version of Earth populated by many inter-related comic series, as well cartoon and film offshoots of the same. The most popular and well-known titles include Spiderman, X-Men, The Avengers, Captain America, The Incredible Hulk, Punisher, Daredevil, and The Fantastic Four in the superhero genre.

The Marvel Universe is more technologically advanced and more magically and psionically active than our own and there are several islands and small countries (especially in the former USSR) that do not exist on Earth Standard.

While a wide variety of superpowers, para-, super-, and ultra-normal abilities, and genetic differences are more or less common in the Marvel Universe, they usually come with unpleasant side-effects. Unfortunately, 'Sue-powers are difficult to classify in this universe. Resurrection and return from death, clones, unknown twins, and tragic pasts/futures/destinies are moderately frequent for main characters. Mutations may be more or less visible to the naked eye, leaving people ranging from baseline human in appearance to drastically altered in shape, texture, and appendage-count.

Earth-616 is home to many non-human (in the sense of homo sapiens sapiens) sentients, including homo sapiens superior, mutants, primarily dealt with in the X-Men titles; the Eternals, a superhuman offshoot of humans; Deviants, the likewise superhuman adversaries of the Eternals; homo mermanus, a humanoid aquatic species; the Inhumans and the Subterraneans, genetically created by the Deviants; and other tags and ends of genetic experiments in forgotten corners of the world. The most frequently appearing alien species include the Kree, fairly militaristic humanoids; the Skrulls, reptilian shape-shifters able to mimic another being's features exactly; and the Shi'ar, humanoids of avian descent.

Gods, demons, and creatures from Earth myth appear with reasonable frequency, though they are occasionally altered somewhat to fit the pseudoscientific reasoning of the universe.

While possible, time traveling to the past to change things merely creates a split in the time-stream (a la the Trousers of Time) and the traveler will generally return to their own future, unaltered from the divergence created in the past. Changes to the whole time-stream, without just creating a split are classified as a Very Bad Idea. Travel to the future is certainly acceptable, but not recommended.