As always, your work is quite impressive. The anatomy (particularly on his chest), and the detail in complicated forms (such as his shoes) are finely rendered. The foreshortening is good, and for the most part the pose is interesting.

I feel that the overall feeling of movement could have been furthered with more consideration to the spine, neck, and head. When leaping like that, do people usually keep so strait-backed? Usually there is something of a curve to the spine in a jump like that. The thickness of his short neck add to this stiffness. Lastly, his head doesn't seem to quite connect with the neck well. I feel like we should see a bit more jaw and less chin. Maybe if his head was slightly turned and upward, but his eyes still looked down on us.

I too have been struggling with improving the dynamic movement in my pictures. To see muscular men looking really dynamic, try looking at Gurren Lagann's art. It has REALLY helped me so far.

This is my favorite piece so far in your series (and that's not solely based on subject matter!). The ethereal color scheme of the background is lent movement by the swirling souls around him, and I am reminded of the underwater world of his beloved Blitzball, a touch not lost on a fan of FFX.

Tidus himself appears accurate to the game design, from his tattered pants to his mismatched gloves, and the two keys to his life, his sword and his ball, are positioned excellently according to the Rule of Thirds. My eye is immediately drawn to the both of them, and continues to move throughout those cool colors of the background. The proportions of his body look correct, as does the perspective of his flying leap.

All in all, I cannot think of anything I would correct for this deviation. Excellent job!