B73-NS is a type of Bastion Siege Automaton. It is an upgraded B73 Siege Automaton modified by by Null Sector. B73-NS appear as enemies in the Uprising game mode under the name B73-N.

Bastion has a B73-NS epic skin available during the Uprising event under the name "Null Sector".


When appearing as enemies in the Uprising brawl, B73-NSs appear in two varieties, the first are the type who run into battle before taking position and re-configuring into sentry mode, the second type appear only in a permanent tank configuration - though deal far less damage than playable Bastion does when using his ultimate. Charging into the tank version of B73-NS won't cancel it out of it's tank mode. B73-NS also notably has a different ultimate sound effect than Bastion does. When a B73-NS appears one of the allied heroes will note that an enemy Bastion has appeared. The enemies also have much more health than the playable Bastion, can't crouch or jump, don't need to reload and react differently when hacked by Sombra.