Absolute Intelligence could transform @BlackSupergenius II into a great person capable of saving the world. However, since that change isn’t guaranteed, I’m not sure the world would actually be saved.
My methods, on the other hand, would be immediate. By accessing an omniscient well of knowledge, I could find the best solution to ensure everyone has a good life. Simply altering a series of events or curing a mental illness could change someone who might have become a murderer or committed other bad acts into a good person.