Complex sentence: Taking on the name of Ainz Ooal Gown, a message to any other players, Momonga begins exploring the world in an attempt figure out what has happened while searching for anyone, or anything, that could help him solve this mystery.
Split into simpler sentences: Taking on the name of Ainz Ooal Gown, a message to any other players, he begins exploring the world. He tries to figure out what has happened while trying to find anyone, or anything, that could help him solve this mystery.