A trailer for the new Diablo III expansion Reaper of Souls has appeared on YouTube.

The trailer has not been released through official channels, and it seems likely that - with Blizzard's annual convention due to start today in California - it was due to be debuted at BlizzCon ...

The trailer shows off the expansions new Adventure mode, which will allow players to take on bounties and "random dungeons" for gold and XP, Nephalem Rifts that teleport you to a "Rift Guardian" boss challenge room, and trailer footage of new artisan The Mystic, whose transmogrification and enchant abilities we covered earlier this month.

You can check out the trailer below to see the expansion's new features for yourself.

Diablo III had a problematic PC launch back in May 2012 when it was plagued by server issues, but the subsequent console releases have been rather more smooth. The Reaper of Souls expansion, which was first announced back in August, is slated to launch in 2014.

Blizzcon is kicking off this evening, so expect lots more Blizzard-related news over the next few days!

What do you think of the new trailer? Does this expansion look like enough to get you back playing Diablo III?