Union

Drive-Union (D発症者（ユニオン）) are humans afflicted with a Crystal on their body. They are collectively known as the D-Union and are under the protection of the Mitsurugi Sector. Drive-Union only appears in XBlaze – Code: Embryo.

Information
Crystal, a rare mechanism that mysteriously generates on a persons body for no apparent reason; the chance that a Crystal generates is only one in ten thousand and, should a person grow a Crystal, the person becomes a Drive-Union.

The Crystal in a Drive-Union's body converts Seithr into a unique ability that the Progressor can use, however, this ability comes at a price: the spirit of the Progressor becomes polluted and leads to extreme erratic behaviour.

For unknown reasons, the Mitsurugi Sector protects, manages and treats the Progressors. Kazuto Kotetsu is somehow involved with the Union.

Trivia

 * Ripper is the only Drive-Union whose spirit hasn't been polluted.
 * Drive-Union shares similarities to Ars Magus users as they draw out Seithr from the air to use for special abilities.