This piece is absolutely stunning! I'll say that right away.
- the pose is very dynamic and much like Zero. - the colouring on zero is absolutely amazing, especially the little glow of the shinryuken on his armor, nice touches -the image is very captivating and not too busy that you can't see Zero
Some minor suggestions - zero's hair is much longer then that and thicker. It's a simple fix, but lengthening his hair some would make that portion just perfect - the way the body twists, you'd see a lot less bottom of his feet. It almost feels he's bending in an odd way. - just some minor tweaks on the 'flames' to make them more firey (not so linear, add some variety of spikes,etc and random sparks)
Thats really all i could see. it's really stunning an amazing peice! I love how you captured Zero in one of my favourite moves <3 Absolutely gorgeous!
Ryuenjin is a Fire Shoryuken but with a sword. The Shinryuken is Ken ultimate techinque, proof of he master the Shoryuken not only creates a flame but at the same time he Spin the entire body as he goes UP creating some kind of deadly fire vortex.
These is pretty much the same but zero is the one perfoming it so maybe..ShinRyuenjin them?