The Spirit Engine looks like a platformer, but it’s a fully realized RPG from a slightly (for RPGs) uncommon viewpoint, if you don’t count action RPGs or platformer with RPG elements (which TSE is neither).
The world is a mix of fantasy and science fiction elements. Three heroes have been summoned to guard a spirit from a mighty corporation who wants to use it for something nefarious. You have to chose wisely at the begin of the game, since only a good mix of different talents allows the team to succeed (you have the choice from nine different characters).
TSE has all the common RPG stuff, experience points plus leveling-up and allocation of skill points on diverse talents, item management and fighting, fighting and more fighting. The battle system is custom-tailored to the 2d-perspective and while it is real time, you can only win if you fight tactically smart.
The graphics are beautiful, on the same level as commercial 2d-games of the past. Overall TSE is one of the best freeware RPGs on the net, melding unique gameplay, a good plot and an excellent look to make it absolutely worth your time.