i was farming skadi daily in under 18 mins (didnt get a single mount to drop btw) until my gametime expired. here are some tricks:

1. try to have a DK tank, they take damage much, much, much better than other tanks. I would pop all my CDs before one of my other guys aggrod skadi, and I didn't have to throw a single heal on the DK tank until skadi came down

2. move all your guys (except 1) to the little room. put them way in the back, drop all your totems, before your outside guy aggros skadi drop magma totems (no threat AOE ftw)

3. always have D&D or consecrate down in that room. otherwise guys run out and all the way down (still can handle it but just easier when you dont)

4. drop healing totems when in the room, switch one to a poison totem when skadi comes down

5. when you can bring your outside guy into the room and facing the right way

5. when the room is cleared (i can do it 1st pass but you can wait till 2nd) have your tank run out with harpoons and bring skadi down, keep D&D down in the room for any adds that spawn during the time you are shooting. have only your tank hit skadi a few times before you start DPSIng, keep healing the tank during this time.

You shouldn't move your guys outside the room at all, just keep skadi in the middle of the outside end area and your guys inside, and just taunt when skadi is halfway between you and your guys -- use two taunts usually (death grip & dark command on DKs) since he will usually bounce back and forth (dont let him get into melee range of your DPSers).

it takes quite a bit of practice, I wiped 40+ times on him with my pally before I kind of got it down, strangely enough on my DK it only took 3-4 wipes and after that i 1-shotted it for 2 weeks straight. Once you get it down, you can do speed runs - skip first two bosses and just do him, takes < 20 minutes.