Board Thread:Dark Souls II/@comment-28684144-20160607210819/@comment-27019589-20170316075222

Keep the giant souls for next NG+ Cycle, they don't offer many souls while being used so it's good to keep them.

There's no reward for farming the entire game.

You can defeat the throne watcher and defender immediately after getting the ring, if you so please, leaving just Nashandra and possibly Aldia for last.

You're thinking of Repel, which is acquired by trading the Giant Lord Soul with Straid of Olaphis, it makes you immune to all damage for about a second and a half, without duration extending Northwarder Set|gear]]/rings.