Season 1 Episode
- Season 1 Beginnings (Origins, Part 1)
- Season 1 To Catch a Queen
- Season 1 Mobodoon
- Season 1 The Price of Freedom
- Season 1 Underground Masquerade
- Season 1 Tangled Webs
- Season 1 The Deepest Fear
- Season 1 Who Do You Think You Are
- Season 1 The Last Resort
- Season 1 Come Out Wherever You Are
- Season 1 Winner Fakes All
- Season 1 A Hedgehog's Home Is Her Castle
- Season 1 Artifact
- Season 1 Bug!
- Season 1 Sonic Tonic
- Season 1 Friend or Foe?
- Season 1 Head Games
- Season 1 When in Rome...
- Season 1 The Jewel of the Crown
- Season 1 Three Hedgehogs and a Baby
- Season 1 Dunes Day
- Season 1 Mummy Dearest
- Season 1 Hedgehog in the Iron Mask
- Season 1 Six Is a Crowd
- Season 1 Flying Fortress (Chaos Emerald Crisis, Part 1)
- Season 1 Wedding Bell Blues
- Season 1 No Hedgehog Is an Island (Chaos Emerald Crisis, Part 2)
- Season 1 Getting to Know You (Origins, Part 2)
- Season 1 New Echidna in Town (Chaos Emerald Crisis, Part 3)
- Season 1 Harmony or Something (Origins, Part 3)
- Season 1 Country Crisis
- Season 1 Haircraft in Space
- Season 1 Healer
- Season 1 Sonia's Choice
- Season 1 The Big Melt
- Season 1 Sleepers
- Season 1 Bartleby the Prisoner
- Season 1 The Art of Destruction
- Season 1 The Pendant
- Season 1 Virtual Danger
Sonic Underground - Season 1 Episode 29 New Echidna in Town (Chaos Emerald Crisis, Part 3)
6.89 25 minutes Knuckles reluctantly makes a deal with Robotnik to turn over Sonic and his family in exchange for finding the Chaos Emerald that will save Mobius. Knuckles soon regrets that he ever trusted the evil dictator after Robotnik begins to follow through on his plans to roboticize the Hedgehogs.
