I recently rerolled from alliance to horde on Onyxia. I am my guild's main tank and raid leader, but having some trouble really finding a solid strategy for beating Panther. Keep in mind, we are mostly in all blues and greens. We can't just simply zerg it with dps and aoe the panthers down when she disappears. There really seems to be no solid way to negate the marks either. What I've been doing is having 2 shamans attempt to get as many panthers on them from the start with healing stream totem, etc. Basically, whatever they can do without actually attacking the panthers. It seems to work decent, but a lot of the panthers still come over to the group. I've played around with fearing, frost nova rotations, etc., but most of the time we get overwhelmed. Our best attempt was 2% after a handful of attempts. The next time we went into ZG we got him down to 17% on our first attempt and 16% on our second. I was just wondering if you would be so kind to give me some advice sicne you've been raiding on horde for such a long time and I've only done a few raids. Any help is appreciated.

Thanks,
Lopihealsme

I don't believe healing stream generates any aggro. Magma totem is quality for this fight although expensive so you'll need to pick your moments. There is probably no better fight in the game for stoneskin totem.

My casual guild puts a tank in each pen and puts one healer on the pair. A bear appropriately geared can hold a swarm fairly well, requiring very rare heals. While marked people do get panthers, it's vastly more manageable than the encounter by default. 3 vanishes is plenty of time to manage with modest if effective DPS.

Edit:

If you got her to 2%, and people are wearing greens, I think the solution is pretty obvious.

Put a Warrior in each pen to hold as many panthers as possible, with a healer on each (pref. Druid).

The offtank Warriors will need to spam as much Demoralising Shout as possible to hold the Panthers. Items which deal damage on being hit (Shield Spikes, various trinkets etc) help immensely.

Make sure the marked person stays against the back wall at all times. You will get some Panthers out on the main group, it's inevitable .. have Warlocks / Priests fear them until the boss disappears, then have your DPS clean them up.

Ya...warrior in the pen on either side. Both shamans with stoneskin, healing stream and goa down, using light heals to proc ancestral healing and heal through zerg damage.

Then zerg her down with the other 16 while fearing/nova'ing/warstomping the ones that get by, and assisst them down when she stealths so as not to burn mana.

We used 3 mages with a frost nova rotation on horde.
Whoever gets aggro from a panther would run towards the gong and the mages would just keep em into place with frost novas. Since we were all shatter specced at the time we would toss in the odd blastwave (lots of crits, yay!) to frag em all at once and get a second of breathing room.
It seemed to work fine, took some communication amongst the mages but with coldsnap and 3 people with half a brain it worked elegantly.
Actually the worst thing about it was the following: someone would run a panther towards us, it gets novaed and then the person just stands there doing whatever (healing/dps), totally oblivious to the fact that they still are taking damage. As if frost nova would completely incapacitate the panther(s).
Once our healers stopped healing them they quickly learned tho :p

What we basically do is have everyone start DPS as soon as she spawns. You don't wait for sunders or anything. Whoever is marked goes in the center of the room. After she disappears, two different things can happen. If the marked person is a cloth or leather wearer (not druids since they can go into bear form), we AoE the panthers. If the marked person is a mail or plate wearer, we just get have a couple of designated healers healing them through the whole fight. Obviously, whoever is marked needs to be healed until it wears off. What tends to happen is the same person stays marked for a reasonably long time if you don't kill the panthers.

EDIT: And everyone besides the marked person should be pretty close to the wall on the opposite side of the gong. The reason the marked person goes to the center of the room is to make sure the panthers don't interfere with anyone else. Oh, and have your locks, priests and warriors AoE fear near the end of the fight when things start to get out of control.

We have used basically this strat since we were in greens/blues (new server you see) and it works fine for the gear level. We have the panther tank run in an oval away from the raid with warriors piercing howling and mages frost nova'ing from time to time so they're not getting quite as beat up. A clothie can even tank them this way but it can be risky. The good thing too is that once the panthers are on a mark they will typically stay on that person even after the mark is gone, and since they stop spawning that person will be able to tank the panthers forever. The only thing is that new marks have to stay at the back far away from panthers or they can attract them onto their mark.

Since you're Horde, have a healer assigned to healing the marked kiter move the marked person into a group with a shaman on the fly for stoneskin totem, and the rest of the shaman keeping up a good earthbind spread. In this case, don't try very hard to kill the panthers while she's gone, just have the rogues keep their SnD rotation and the warriors build up rage for when she appears. Controlling the panthers is far more important in your level of gear, than keeping them down.

And of course, as everyone said, Flash Bombs.

As we are at BWL level these days, we just dont worry too much on Arlokk and we DPS the hell out of her. But it was not always like that, we had to do it too in blues/greens.

Panthers can be handled during the first vanish but they become a real problem on the second one. Flash bombs and all the others gadgets you can use to gain some time while she vanishes are the key (ie. thornling seeds from DM work great and last just long enough).

If the marked person is not in a group with a shaman, switch him/her as soon as possible . Make sure a lock is in that group too. Stoneskin + imp buff does quite a lot to preserve a squishy from being torn apart by panthers. We never did any fancy kiting strategy around the room as its very small and you just cant see anything with all the AOEs. Everybody is grouped toward the gong and the MT just runs around frantically to make sure he gets Arlokk when she gets out of stealth.

IMHO, it's not the best ZG encounter..

We have everyone group up (basically on top of each other) and two warlocks use hellfire for the entire encounter (lifetapping when needed). MT keeps Arlokk away from the group, everyone focuses on the boss and the healers keep the warlocks up.

It all works pretty well.