|Your name's Percival?|
Dark Qwark was a skin for Qwark in the Qwark vid-comics which represented Qwark but was, like the name implies, darker. It could be unlocked by entering the Tutu Qwark cheat code twice while playing a Qwark vid-comic.
The skin was likely a glitch, as the developers likely never thought of entering the Tutu Qwark cheat code more than once.
- Ratchet & Clank: Up Your Arsenal (first appearance)