In this case, the animation for elves, Hands.(ModelInstance)_Idle00-LOD.xdb, is bugged. Other animations don't seem to cause problems.
Simply deleting the animation won't solve the problem, as I've found a similar situation with Necropolis and Inferno (these factions have characters with animated models).
The nature of the bug is still unclear to me. As soon as I find a solution, I will release a bug fix.