The DIE-wing, as it was derisively described, was a type of homegrown starfighter (otherwise known as an "ugly") that married the ball cockpit of the Imperial TIE fighter with the engine nacelles of the Y-wing. The resulting combination basically incorporated the weaknesses of both designs and the strengths of neither, meaning that the DIE-wing could easily be PWN3D by the original configuration of the Y-wing. Just between us, that's saying something.
Of course, since TIE cockpits are the third most common element in the galaxy, next to hydrogen and stupidity, the design's shortcomings didn't stop pirates and other kinds of spaceborne criminals from building them in droves. Rouge Squadron pilots loved to engage them in battle, taking bets on who could vape the most DIE-wings in under thirty seconds.