Beta and Gamma

Beta and Gamma are two dogs led by Alpha and are minor antagonists in Disney/Pixar's 2009 film Up. Beta is voiced by Delroy Lindo and Gamma is voiced by Jerome Ranft.

Up
Beta and Gamma are Alpha's 2nd- and 3rd-in-command. Beta is a Rottweiler and Gamma is a Bulldog. Like Alpha, they both wear a translation collar that enables them to talk. They were sent on a mission to find a giant bird and bring it to their master. Apparently, Dug was initially assigned this special task because he was a disgrace to the pack, and they wanted him gone.

Beta and Gamma later encounter Carl Fredricksen, Russell, Dug, and Kevin and take them to their master, who turns out to be and elderly Charles Muntz, Carl's childhood idol. After learning about Russell's friendship with Kevin (the bird), Muntz furiously sics Beta, Gamma, and the rest of the pack on the four misfits.

Beta and Gamma are seen again driving airplanes. Outside, Russell sees Carl and Kevin in trouble. Encouraged, he manages to climb to the porch of the house. Planes continue to attack, but he manages to stop the planes by calling out that he sees a squirrel; this distracts Beta and Gamma (and another dog) and makes them collide all of the planes, though the dogs parachute to safety.

Beta and Gamma are briefly seen playing poker in Muntz's Spirit of Adventure airship, which is a parody of the famous "Dogs Playing Poker" series of paintings by C.M. Coolidge.

Beta and Gamma are last seen among the other dogs at Russell's ceremony. They howl with approval after Carl awards Russell the grape soda badge from his deceased wife Ellie. Presumably, Beta and Gamma become Carl's pets in the film's credits.

Dug's Special Mission
Beta, Gamma and Alpha are tripped by Dug, causing them to lose Kevin. When Alpha gives Dug "special missions," Beta and Gamma show support, but they get hurt along the way and almost killed. They eventually leave Dug while Alpha calls "master" to tell him that Dug caused them to lose the bird, and that he is a bad dog.

Trivia

 * Beta and Gamma are two of the three types of radiation in real life, along with Alpha.