The only way to beat the giant Beta is via direct attack to the brain, forcing Ogre into a very perilous situation. Auctioneer risks his life to locate the brain, and Ogre uses Number 11 to take it out and defeat Beta.

He reunites with the Squad and celebrates, but his joy would be short-lived.
I have a duty to see 
how this whole thing plays out.
فلديّ واجب متابعة كلّ هذا حتّى النهاية
Seré testigo de esto hasta el final.
Seré testigo de esto hasta el final.
Tenho o dever de acompanhar isso até o fim.
Я должен увидеть, чем всё обернётся.