Another of the Kargan mecha from the ol' Mekton II Technical System.
Here's the lineart (a study of the original): [link]
And here's it's weapon, the "Ramzooka": [link]
The original Photoshop file uses a ton of layers and channels, so that the robot can be depicted with or without the weapon, ammo clips, and shield in any combination. (Take a look here [link]
to see what I mean.) Also, the background is the Mekton Z RPG's official stat-sheet... which I designed myself, way back when. This amuses me.
Mekton, Karga, and the IMK-05 Rampage are property of R. Talsorian Games. No infringement intended nor implied.