Dominion (mirror)

In the Mirror Universe, the Dominion is even more savage and ruthless than its counterpart in the Federation universe.

For example, the Founders of the mirror universe would never have tolerated defiance from the people of the Telpan System by merely inflicting them with the "blight". (DS9 episode "The Quickening") Instead, they ordered the entire mass extermination of the planet's population by using a different biogenic weapon. Within two weeks, the inhabitants had perished to the last man, and the planet was cracked open to be mined of all its mineral wealth, leaving behind a completely dead world. Such a brutal act was intended to be a reminder to all who opposed the will of the Dominion.

Even the servants of the Founders differ in the mirror universe. The Jem'Hadar are larger, stronger, and even more suicidally devoted to their masters. As for the Vorta, they are far more vicious, and possess more advance teleknetic abilities to use as either diplomats or assassins. Perhaps the only similarity with the Dominion of the Federation universe is that its mirror counterpart is aggressive and expansionistic. (Through a Glass, Darkly)