Amaterasu hasn't been warped yet. Her main goals are a life of godliness (That means sitting around and basking in worship, quietly.).

Her real goal is Suicide, actually, as she has a massively nasty Dark virus in her. Or possibly Dark Mist. She's got something really really nasty inside her, and she wants to let it die with her.

If the virus is purged out her, it depends on where she goes, but she might do anything from make Japan float in the air to protect it from the oncoming deluge of the rising seas, to transporting her ruined kingdom to this world.