Location: Deepholm. West side of the Temple of Earth. Then the hard part, the z-axis. The entrance is about two-thirds of the way up the central pillar. There’s a distinct landing platform once you get to that level or higher. Cataclysm Dungeon Location Gallery.
The first few pulls of the instance involve Millhouse Manastorm with a group of 3-5 other enemies. The Stonecore Earthshapers should be dealt with using crowd control or by killing them first. The Earthshapers have an ability with a long cast time (called Force of Earth) to turn into a large Earth Elemental; it needs to be interrupted, as a transformed Earth Elemental can quickly decimate the party with Sandstorm. Attack Millhouse Manastorm next; in these fights he is more of an annoyance than an actual threat, but with his wide array of both direct and AoE damage spells he is still more of a threat than the rest of his cohorts. Once Manastorm's health reaches halfway, he will run off to the next group and await the party there, leaving you to mop up the rest of his friends in the current fight.
Roaming bands of small, non-elite earth elementals will often aggro onto the party during these pulls. These deal little damage and can be killed easily with AoE.
Once the party has dealt with Manastorm a number of times, he is then backed into a corner, where he is quickly squashed by Corborus.