The Ordinatus Eternum (or-di-NAY-tus e-TUR-num)

The Ordinatus Eternum was equipped with a variety of advanced weapons and systems, its main weapon a Macro Plasma cannon, lascannons, and multi-meltas. It also had a heavily armored hull and powerful shielding, making it nearly impervious to enemy attacks. In addition, it was equipped with a number of advanced sensors and targeting systems, allowing it to accurately target enemy units at long range.
  Despite its impressive capabilities, the Ordinatus Eternum was lost during the Horus Heresy, when it was deployed to the front lines of the war against the Traitor Legions. It is not known exactly what happened to the Ordinatus Eternum, but it is believed to have been destroyed in battle or lost in the Warp.
  The loss of the Ordinatus Eternum was a major blow to the Imperium, as it represented a significant loss of resources and technology. It is said that the Adeptus Mechanicus searched for the Ordinatus Eternum for centuries after its loss, hoping to recover it and reclaim its advanced technology for the Imperium. However, it was never found, and its ultimate fate remains a mystery.