Sonic Boom - Season 1 - Eps 31: Closed Door Policy
When Amy realizes that Sticks is a pack rat, she forces her friend to have a garage sale to get rid of all the junk that's accumulated in her burrow. During the sale, a secret locked door to an underground world is removed and an invading horde is set free.
About Sonic Boom

Title: Sonic Boom
First Air Date: 2014-11-08
Last Air Date: 2017-11-11
Status: Ended
Rating: 7.426/10 (from 352 votes)
Language: EN
Seasons: 2
Total Episodes: 104
Network: Cartoon Network Boomerang
Genres: Action & Adventure, Animation, Comedy, Sci-Fi & Fantasy, Family
Production Companies: OuiDO! Productions, Technicolor Animation, SEGA of America
Synopsis
The speedy blue hedgehog Sonic with sidekick Tails and pals Knuckles, Amy and Sticks tries to ward off the evil plans of Dr. Eggman, who is hellbent on taking over the world. Sonic faces regular battles with Eggman's henchmen, including loyal robots Orbot and Cubot, evil interns, and giant, robotic monsters.
Cast

Roger Craig Smith
Sonic / Dave the Intern / Young Gogoba (voice)

Colleen O'Shaughnessey
Tails / Zooey / Mrs. Vandersnout / Belinda (voice)

Travis Willingham
Knuckles / Soar the Eagle / Obliterator Bot / Old Monkey / Mr. Slate (voice)

Cindy Robinson
Amy Rose / Perci / Elderly Gogoba / Justin Beaver (voice)

Nika Futterman
Sticks / Diane Aardvark (voice)

Mike Pollock
Dr. Eggman / Fastidious Beaver / Mayor (voice)

Kirk Thornton
Orbot / Shadow the Hedgehog (voice)

Wally Wingert
Cubot / Gogoba Chief / Dixon / D.B. Platypus (voice)

Bill Freiberger
Comedy Chimp / Lady Walrus (voice)