Players have a Climbing skill which influences many of the factors of climbing, such as the likelihood of being knocked off of a surface upon taking damage. (Any other effects ?)
Players initiate climbing by walking against the object they want to climb or scale, and the character will automatically grab on. You climb slower than you run or walk, and your character loses Endurance while climbing, so watch your endurance bar carefully when going for a climb. While you are scaling a surface, such as a rock wall, you have omni-directional movement so long as the climbing area permits it and you can stop climbing at any time. When you stop climbing, your character will hang from the surface (does this cost endurance?). Currently, there is no limit to how long your character will hold on to a surface.
There is no player collision while Climbing, so you cannot block/knock or be blocked/knocked off of the surface while climbing with other players.
You can gain aggro while climbing, and maintain any aggro you already had.