This is a piece I did on vellum bristol board with a magic marker for the heavy lines, a black micron pen and prismacolor markers.
This is likely one of my most detailed isometric pieces to date, perhaps seconded by another piece too big for me to scan on my own atm.
The piece is a concept art contribution for the game Infinity; the Quest for Earth. It depicts a superlight raider ship that relies primarily on armor defenses and its superior speed to deliver firepower on target. Not depicted here are a number of guns. You can see where they'd be attached on the top of the ship, the flanks and the front of the weapons nacelles. The two alternate nacelles below the attached ones are different module options that perform various other enhancing functions for the ship.