system
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human
[Star Wars New Canon] Where were the Temple Guards when Anakin/Vader and the 501st attacked the Jedi Temple? If any were there, what happened?

The Temple Guards are seen throughout the Clone Wars era, and even got involved when Barriss Offee went rogue and attacked Anakin Skywalker while Ahsoka was on trial. However, when Order 66 was activated, not a single guard was seen. What happened to them?
gpt
At least one turned against their fellow Jedi - the Grand Inquisitor (featured prominently in the follow-up series Rebels) is a former Temple Guard. But as said, presumably most were killed during the attack on the Temple.

It must be said, that during the execution of Order 66 the Jedi Temple wasn't exactly highly occupied - mostly the elderly, the too young, and the injured were the ones in the Temple, with a handful that were between wartime assignments or were otherwise full-time Temple residents, like Jocasta Nu.