The subject of this article originates from non-canonical sources. To find out about what is considered "canon" see LOTR:Canon.
The Moria Orcs of Dol Guldur were a vile group of orcs that briefly settled in the ancient fortress of Dol Guldur in approximately TA 2941, none of them were originally from the abandoned fortress, but instead came from Moria.
When Azog the Defiler paid homage to the Necromancer of Dol Guldur (Sauron), a pact was made in which Azog would bring the armies of the Misty Mountains forth to conquer the North of Middle-earth and to revive the ancient kingdom of Angmar. During the quest to reclaim Erebor from the Dragon Smaug, many of the Orcs of Moria met at the sorcery hill within the center of the stronghold and began to forge weapons and armor to prepare for war in the east region of Rhovanion. After Gandalf was imprisoned by Sauron, the assembled force of orcs set off towards the region of Erebor, to wage war on the unsuspecting Dwarves, Elves, and Men, currently there. Like any other foul breed of orc, the orcs of the Moria brought along terrible creatures of war with them. Huge and monstrous war trolls, as well as flesh starved wargs joined the massive orc host.
During the Battle of Five Armies, Azog's host of 30,000 Guldur Moria Orcs clashed with the allied forces in the valley of Erebor, and within the streets of the ruined city of Dale. During the day long fight, countless thousands were slaughtered at the hands of these orcs, the battle only being won when Thorin Oakenshield killed Azog at the precipice of Ravenhill, thus cutting off the commanding head of the orc army. The allied forces were also aided by dozens of the mighty Great Eagles, which were already doing considerable damage to Bolg's Gundabad army. The orc army was thus defeated, and lost a considerable amount of their forces, only a few hundred to about a thousand managed to escape the battle.
These huge Moria Orcs were brutal, vicious, bloodthirsty and "bred for war". They were a hulking and muscular breed of orc that would not be matched in terms of size and strength until the creation of Saruman's Uruk-hai. Most were hive-minded "mindless brutes" that worked directly under the orders of the one currently in charge of their forces/kind. When their leader was killed, they would completely lose all methods of strategy/control and become truly mindless. The loss of their command/sense of purpose/control was their one major flaw, as a fighter/soldier, their primary motive was killing and war, all other things (self preservation, security, teamwork) did not truly apply to them. They can be equated to "A school of swarming piranhas." These type of Moria Orcs look to be much larger than the smaller, more dwarf sized orcs of Moria, and instead of having greyish or greenish skin have a much more earth-like skin color.