|Jafar says: Read my lips and come to grips with the reality!|
The B73 units were the primary Bastion unit used by the Omnium army during the First Omnic Crisis . All of the Bastion bodies found in Eichenwalde are labelled "B73", suggesting that all of these units were the same type. This version is also a playable skin for The E54 model bastion in the 2016 videogame Overwatch.
The B73 bastion units wanted nothing more than to wipe out the Human race so that the Omnics can own the planet. They are single minded in the goal of wiping out the humans.
The B73 bastions were sent to attack the world along with larger Omnics during the first Omnic Crisis the most notable conflict was the battle of Eichenwalde, destroyer aircraft and the new Bastion E54 (the only one of its kind on record),The B73 units along with OR14s and other war machines marched through the forest to engage the German army, led by Balderich's Crusaders.
For unknown reasons the E54 shut down in the forest, remaining inactive even long after the conflict, only to awaken with sentience years later.The B73s fought the Crusaders, with many casualties on both sides, eventually the B73s as well as the OR14s reached the castle and killed Balderich, however they were unsuccessful in the invasion thanks to the valiant efforts of the Crusaders.
The B73 remains were left throughout the abandoned castle town and were still there even years later. However 20 years after the crisis Null Sector used upgraded B73s during the Kings Row Uprising.