Diablo II's developers at Blizzard North have been busy working on the expansion to the game even since before Diablo II was released. These concept drawings show some of the characters, monsters, and settings that they've been working on. You'll see renditions of the new assassin and druid character classes, as well as sketches of some of the game's monsters and unique landmarks. Though Blizzard already has a lot to show, the Diablo II expansion isn't slated to ship until the middle of next year - so stay tuned for additional information.