Diablo 3's annual nostalgic celebration of bloody pixels is back for another year. The Darkening of Tristram kicks off today at 4 p.m. PST and runs through January 31 at 4 p.m. PST.

"The Darkening of Tristram" is an annual event in which a time-traveling portal from "Diablo 3" will be simulcast into a 16-level dungeon beneath the Tristram Cathedral in the original "Diablo." Beyond the portal is a pixel-filtered vision of the past that mimics the sprite-based style of the old Diablo games. The dungeon features classic monsters like the demonic Butcher and unique rewards for exploring the new area. If you like, you can read the Diablo 3 Darkening of Tristram Secret Guide.

This mode is pretty awesome, and if you didn't care for it before, or if you started Diablo 3 after last January, you should definitely check it out. It's an especially good way to level up new characters, as you can rack up huge kill chains. We're big fans of the game, and we had our doubts about the future of the series when it debuted a few years ago. For more thoughts on the mini-dungeons, check out that article.