Gareth (ガレス), also known as Blitz (閃撃), is a regimental commander of Red Constellation.
In S.1207, Gareth was asked by Shirley to help train Cedric Reise Arnor. Working with Gilbert Stein, the commander of the 6th Enhanced Jaeger regiment, the two groups were sent to the Temple of the Moon to begin the training session. When Cedric hesitated to start the session, Gareth fired a warning shot at his feet to force him. Cedric was eventually able to realize what had been holding him back and eventually reached the two commanders, where Gareth supported Gilbert from afar.
Cedric defeated Gilbert and was satisfied with his victory. Gareth was also satisfied with how fast the fallen prince had matured, only to become upset when Gilbert refused to accept the loss and summoned his G-Apache. He tried to intervene, but Shirley appeared and ordered him to stand down. Gareth watched as Cedric defeated Gilbert a second time.
When Crossbell's rebels attacked the city to retake it from the Supreme Leader and the Black Guard, Gareth was contacted by Dieter, who requested his services. Gareth was impressed that Dieter reached out to the corps again and accepted the lucrative offer, working with the rebels to liberate the city.