Maybe Rumple will give up his dark one magic to try and save Gideon.
This would make a lot of narrative sense. We’ve already seen Rumple give up his life to save his family in S3, but I think him giving up magic and continuing to have to live without it would be a greater sacrifice. The’ve always shown it to be his crutch. S1 showed Rumple choosing magic over his son, so it would make sense for them to set up his full “redemption” to be have to make a choice and choosing his son over magic this time.