On oblivion you have to defeat the dark seducers you have killed them all but you cant do anything else help?

If you've defeated all the Dark Seducers in "Oblivion" and cannot progress, try leaving the area and returning to reset the enemies. Alternatively, check if you need to trigger a specific event or interact with an object to continue the quest. If you're still stuck, consider reloading a previous save or consulting a guide for that particular quest.