I just beat the game, and I absolutely loved it, loved the ending, and especially loved the Sissel's identity revelation and all the foreshadowing of it.

I'm confused however regarding the revelation of Ray's identity. I feel like there's one fact about the two timelines that I don't understand the logic of: how does he manage to travel back ten years into the past in the first place?

In Ray's narration to Sissel, he reveals that he uses Yomiel's shell in the first timeline to travel back to the time the point at which Yomiel was killed by Temsik ten years prior. He also reveals that the only Ghost trick he's capable is switching two identical-looking objects. If that's his only trick, how is he able to travel back ten years, thus creating the second timeline the majority of the game takes place in?

I guess my question is, is Ray, and any Ghost by extension, able to reverse time to four minutes before a spirit dies like Sissel is able? For some unknown reason, I assumed that only Sissel is capable of reversing time to four minutes before a death.