The SST Laboratories E54 Siege Automaton "Bastion" were the most elite type of SST Laboratories Siege Automaton.
The E54 Siege Automatons had very tough armor, to the point that Torbjörn stated that rifles would have about as much an effect on them as throwing rocks would.
During the Omnic Crisis, E54 Siege Automatons were deployed by the Omnic rebel army as their elite soldiers, causing difficulty to even the best militarizes in the world.
After the crisis all of the E54 Bastion Siege Automatons were destroyed, with the exception of one who lay dormant in the Black Forest - who awoke with self-awareness and became known by the name "Bastion".
E54 "Bastion" Edit
- Main article: Bastion
Initially the E54 Bastion Siege Automaton who would come to known by the name Bastion was identical to any other E54 Bastion Siege Automaton. However Bastion evolved beyond it's programming, gaining self-awareness and a personality. Upon being taken in by the engineer Torbjörn, Bastion was given a new white, green and red/orange paint job and improved Ironclad armor.