I like the picture. You captured the overall "look" of Frost and Sub-Zero well. The simple black and white used to color it didn't take away from the drawing, IMO, and it usually does.
My suggestions for next time is working a bit more on the proportions of the characters' bodies and fleshing out their features a bit more. For example, Sub-Zero's hands are too small and I think Frost's legs came out a bit chubby. Next time, focus on adding some extra lines to the characters' various body parts to show muscle, curves, and more definition.