Steam News announces a sale on Duke Nukem 3D: Megaton Edition, as 3D Realms' old-school 2.5D shooter is being offered for 60% off. There's also surprising news of a new add-on for the game bundle almost 18 years to the day after the original Duke 3D shareware release (which was January 29, 1996, according to Wikipedia). Word is: "Additionally, Duke Nukem 3D has just been updated with online multiplayer deathmatch and cooperative modes! Hundreds of maps are also now available via Steam Workshop!" Word is the game now supports cross-platform multiplayer in versus and co-op modes for up to 8 players. Here's a new trailer celebrating the news.