This a practice thumbnail that I recreated using @i5k 's MM2 thumbnail, so check him out if you haven’t already, he does really awesome work. Also want to thank @Wizzardofaz for helping me create it, great artist and person.
This doesn’t look good.
The lighting is intensely bright
The posing is fine but needs some tuning up to fit an actual humanoid body
The camera angle makes it look dull
The screen dust is pointless
The effects like the electricity are okay I guess.
It’s pretty nice for a first thumbnail, however, there are a few things that could be better. First, the lighting is quite bright. The particle effects are kind of weird-looking. And Nik is holding that knife rather weirdly.