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 know we'll meet again.
سنلتقي مُجدداً بالتأكيد
Wir werden uns wiedersehen,
davon bin ich überzeugt.
Nous nous reverrons, j’en suis sûr.
Ci incontreremo ancora... 
Sicuramente.
Sei que vamos
nos encontrar de novo.
Я знал, что мы свидимся.