This game is awesome, the controls are smooth, the upgrade and unlock system isn't broken or inadequate so you can't notice the effects, but what makes it for me is the Vivi costume you can unlock.
I'm honestly interested in a sequel, the game has potential to it and an interesting story. Some of the enemies were bulls#!*, but I liked the challenge.
When you complete all the levels on optimum, it gives a much more detailed look at what the two spirits combine to form. Really cool game, nice music and graphics, and puzzles were fun yet challenging. 5/5
Here's some info for you guys that are confused as to how you get to rank 25: The rank is a step on the in game achievements, not your characters level. Upvote if this stumped you at first as well.
 "Rogue Soul 2"){kind=icon}
 "Elventales: The Arcanery"){kind=icon}
 "Spirits of Elduurn"){kind=icon}
 "The Deepest Sleep"){kind=icon}
 "Cardinal Quest 2"){kind=icon}
 "Effing Worms - Xmas"){kind=icon}
 "3 Slices"){kind=icon}