So I started editing this, and things got a little out of hand; I'm a big fan of Dark Souls and especially Artorias and Sif so I got really into it >.>
I felt your composition was off, or could be done better in a few areas:
- focal point
While it's obvious that Artorias and Sif are the most important part of the scene, the stand alone sword grabs our attention in part to its strong silhouette and its awkward placing squished between the humanity sprites. Artorias left his greatshield with Sif, but I feel quite sure he would not leave his sword unattended.
- Artorias's pose
It's not necessarily bad, but if you notice, he's placing a large amount of weight upon his mangled arm, which would hurt like hell if he was even able to do it all. A reclining pose of sorts is probably possible, but I opted for him on his knees huddled over Sif with his right arm bearing his weight behind him.
This is another thing where personal preference weighs heavily, but Dark souls is such a classical high fantasy game, with Artorias having such a tragic story, that I thought the composition should match. Sif, the shield, and Artorias form a triangle ( which is often used in classical/ religious compositions) with the sword reinforcing the shape at it's Apex. A vertical composition allows the humanity sprites to better surround and loom over the characters.
There is also a lot of color reduction, optimization, and lighting improvements that could be made. I think the concept and feeling of the piece are really solid and hope to see you work on it further! Feel free to take any or none of the ideas I brought in my edit.