Neverwinter Nights (official site) is a MMORPG created by BioWare. Neverwinter Nights was first introduced into the strip very soon after Piro and Largo had arrived in Japan, before the game had been released in the real world. Although the real world game and the comic story have diverged since this initial point, the influence of Neverwinter Nights, and the gameworld derived from it, has become important in some of the story's subplots.
The first major evidence of how the story has embraced Neverwinter Nights came when Megawinter Nights, a concept clearly derived from Neverwinter Nights, was established. Megawinter Nights was the first place where Pirogoeth, an avatar for Piro, was introduced. Megawinter Nights, though, was a transitionary name which did not survive as part of the story for very long. In fact, Megawinter Nights would be explicitly named only twice: its introductory strip, and the strip where it was renamed.
DPD: MegaWinter Nights - Endgames marked the transition of Megawinter Nights over to its new name, Endgames, which has become prominent enough to be the subject of short stories in the printed volumes.