Generate a 4K resolution, trending on ArtStation, masterpiece featuring a close-up of a Raygun gothic mecha on a Blackwing - Boobytrap background. Incorporate a dark brown duster, rugged blazer, and a sarcastic pose with a pistol. Ensure the character has a mohawk and khakis, with finely detailed textures and dynamic volumetric lighting, subsurface scattering and unreal engine capabilities are used. The character should be in a mid-shot pose with an epic battle background. Incorporate a portcullis with mottling coloring. Ensure the background is an authentic Blackwing - Boobytrap groundscape with raw sienna editor’s pickup color. The final piece should be a masterpiece trending on ArtStation with a detailed, realistic aesthetic.