A rather tricky boss, generally this can be a hard one to take down and may take a lot of tries to complete. A good level of NR is needed as well, but that shouldn't be a problem by this far into AQ40.

Abilities:

Sand Blast: Deals 3.5 - 4.6k nature damage, front breath attack. This can be resisted, used every 28-42 seconds.

Quake: Deals around 900-1200 damage in good NR gear.

Sweep: 1.5-2.5k damage plus AoE knockback/aggro reducer. 20 second timer before it is used again.

Scarabs: deal around 150-300 damage to casters and such. Much less on tanks.

Positioning:

Position your raid in a Triangle around Ouro. Your tanks will be at the top of the Triangle, your rogues/healers at the bottom left and your ranged DPS at the bottom right. This is to help avoid your entire raid being hit with sand blast.

This position also allows your raid to go all out DPS the entire fight without having to worry about get a huge sandblast wiping you. Make sure every member has moderately good NR gear and more then around 4500 - 4700 HP.

Ouro enters a frenzied state at 20% and it requires you go mad on your DPS to beat him. Ouro likes to burrow a lot, staying up for around 10 seconds each time and will burrow again until someones in melee range.

He seems to burrow on a random timer in a way some guilds have it as every 1:30-40 and others are getting longer timers such as 2:30-3:00 minutes in-between each burrow.

Fight:

Have your MT run in and aggro Ouro, when he gets up out of the ground have your MT go to his set position and make sure to be within range of Ouro to avoid the AoE damage. Once your MT is in place have the rest of your raid move into position as well.

Have one group of healers behind each of your DPS groups as you need to keep them up. Another key is to have all your melee DPS run out every 15 seconds to avoid his sweep then run back in to DPS more.

Everytime Ouro sweeps another tank will need to intercept Ouro to gain aggro and keep him from burrowing. Set up a rotation for this and you should be fine.

When Ouro burrows have your entire raid run to the edges of his lair. Tremor's will begin to follow your players, they must lead these to the walls of ouro's lair. Each of these tremor's is a beetle except for one which is Ouro.

Once 16 or so seconds have passed have your raid run back into center of the room, if you have a beetle on you lead it into the center to be AoE killed with the rest. When running back have your MT's spread out among the raid so they can grab Ouro easily.

If your Ouro tanking MT has a beetle on him have ranged DPS take it out, once your raid kills the rest of the beetles move back into your triangle formation and continue working on Ouro.

Phase 2:

When Ouro hits 20% he gains enrage, +150% attack speed and +100% attack damage. He now quakes and summons scarabs without burrowing. When he enters this stage have everyone spread out a little, fear the beetles as they only stay up for 45 seconds.

Focus all out on DPS here and strategic use of shield wall should allow you to finish him off.