Sonic Underground (1999–1999)

1. S01E01Beginnings (Origins, Part 1)August 30, 1999 8.0The history of the Underground is told in detail, from the fall of Mobotropolis to the rise of Robotnik. Included, is a prophecy, as told by
2. S01E02To Catch a QueenAugust 31, 1999—The Hedgehogs begin to learn the important lessons of what it takes to be a freedom fighter.
3. S01E03MobodoonSeptember 1, 1999—Manic, Sonic and Sonia must end their training early when Robotnik threatens the Oracle and takes a member of the resistance hostage.
4. S01E04The Price of FreedomSeptember 2, 1999—Sonia travels to east Mobius to visit her friend Mindy at the LaTour Estate. After being given a watch by her friend Mindy, Sonia discovers
5. S01E05Underground MasqueradeSeptember 3, 1999 8.0Sleet and Dingo plan to collect the taxes owed to Robotnik from the Duke of Velcronia but keep it for themselves. To avoid the wrath of Robo
6. S01E06Tangled WebsSeptember 6, 1999—The sinister Robotnik blackmails Cyrus, an old friend of Sonic's, by holding his father hostage. Robotnik makes Cyrus gain the Hedgehogs tru
7. S01E07The Deepest FearSeptember 7, 1999—On a trip to Port Mobius, Sonic, Manic and Sonia are told that ships are sinking due to the Mobian sea-beast. The legendary story becomes fi
8. S01E08Who Do You Think You AreSeptember 8, 1999—Queen Aleena's royal journals are rumored to be buried under a palace in the city of Tashistan. As Sonic and his siblings scour the city in
9. S01E09The Last ResortSeptember 9, 1999—While lost in the wastelands of Mobius, Sonic, Manic and Sonia stumble upon an oasis called Lake Valley Resort. Although Sonic is impressed
10. S01E10Come Out Wherever You AreSeptember 10, 1999—Sonia is invited to a debutante ball, but before she can be officially announced to society, she and her brothers, Manic and Sonic have an i
11. S01E11Winner Fakes AllSeptember 13, 1999—Robotnik organizes a track meet to lure Sonic into a trap. Robotnik is sure that Sonic will not sit out on a challenge of quickness. Sonia a
12. S01E12A Hedgehog's Home Is Her CastleSeptember 14, 1999—The Hedgehogs receive a message they believe is from their cousin. In the message, a castle is left to Sonia, who revels in the idea of havi
13. S01E13ArtifactSeptember 15, 1999—The Hedgehogs steal historical artifacts of Mobuis from Robotnik before he can pawn them off at an auction. Sonic and Sonia take one of the
14. S01E14Bug!September 16, 1999—A faction of the Freedom Fighters is wiped out by a swarm of metallic fly-bots. When Manic goes in search of the insects, he is stung with s
15. S01E15Sonic TonicSeptember 17, 1999—A speed enhancing fluid deemed Sonic Tonic is created by Robotnik to make him as fast as Sonic so that he may finally catch him. Robinik's p
16. S01E16Friend or Foe?September 20, 1999—The Hedgehogs converge on the Floating Island, in their latest attempt to find their Mother. Sleet and Dingo also have an interest in this i
17. S01E17Head GamesSeptember 21, 1999—As Sonic begins to chow chili dogs for a snack, he finds a message in the sack from his mother urging him to head to Speedster Island. When
18. S01E18When in Rome...September 22, 1999—Sonic becomes frustrated that maybe all of their efforts of fighting for freedom seem futile. Sonia suggests that they go to Oracle, the spi
19. S01E19The Jewel of the CrownSeptember 23, 1999—Robotnik has his sights set upon Queen Aleena's crown jewel, which glows as it is moved closer her. Sonic, Manic and Sonia plan to recover t
20. S01E20Three Hedgehogs and a BabySeptember 24, 1999—Sonic, Manic and Sonia find an abandoned baby in an alley and begin a search for the baby's parents. Manic grows particularly fond of the ch
21. S01E21Dunes DaySeptember 27, 1999—Sonic and his siblings travel to the outskirts of Mobius to recruit a tribe of nomads for the Resistance. The Hedgehogs van breaks down and
22. S01E22Mummy DearestSeptember 28, 1999—Sonic, Manic and Sonia invade Robotnik's lair to retrieve the Hedgehog crest. After the book is reclaimed, they discover that this book cont
23. S01E23Hedgehog in the Iron MaskSeptember 29, 1999—The Hedgehogs latest quest to find their mother takes them to the prison tower where they encounter a masked stranger who insists he is fami
24. S01E24Six Is a CrowdSeptember 30, 1999—The Oracle advises the Hedgehogs to undertake a mission which could reveal answers about their future. Sonic, Manic and Sonia are thrown int
25. S01E25Flying Fortress (Chaos Emerald Crisis, Part 1)October 1, 1999—What is supposed to be a vacation for Sonic, Manic and Sonia turns into a battle to save Mobius when Robotnik attacks with his newest weapon
26. S01E26Wedding Bell BluesOctober 4, 1999—Robotnik announces that he will marry Queen Aleena in a plot to become the king of Mobius. Upon hearing the alarming news and shocked that t
27. S01E27No Hedgehog Is an Island (Chaos Emerald Crisis, Part 2)October 5, 1999—Sleet and Dingo escape the Flying Fortress with the Chaos Emerald. In a fight over who will control the Emerald's power, Sleet and Dingo dro
28. S01E28Getting to Know You (Origins, Part 2)October 6, 1999—The Hedgehogs begin to learn the important lessons of what it takes to be a freedom fighter. The Oracle provides teachers to guide Sonic, Ma
29. S01E29New Echidna in Town (Chaos Emerald Crisis, Part 3)October 7, 1999—Knuckles reluctantly makes a deal with Robotnik to turn over Sonic and his family in exchange for finding the Chaos Emerald that will save M
30. S01E30Harmony or Something (Origins, Part 3)October 8, 1999—Manic, Sonic, Sonia must end their training early when Robotnik threatens the Oracle and takes a member of the resistance hostage. During th
31. S01E31Country CrisisOctober 11, 1999—Queen Aleena advises the Hedgehogs to travel to a valley of Mobius so that they can bring about peace between two contingents of the resista
32. S01E32Haircraft in SpaceOctober 12, 1999—Robotnik is using the local hairdresser, Doo-bot, to get information on the citizens that are against him. Sonia becomes a victim of the Doo
33. S01E33HealerOctober 13, 1999—A self proclaimed scientist has come to Robotropolis with a device that will reverse the effects of Robotnik's roboticizer. Sonia, Manic and
34. S01E34Sonia's ChoiceOctober 14, 1999—Robotnik has arranged a museum exhibit of the Royal family goblets. Knowing that Sonic, Sonia and Manic will want to reclaim their family's
35. S01E35The Big MeltOctober 15, 1999—The Hedgehogs vacation is interrupted by the news of Robotnik's latest weapon. They are shocked as the submarine melts the icy landscape fro
36. S01E36SleepersOctober 18, 1999—On a mission in a distant sector of Robotropolis, the Hedgehogs are informed that freedom fighters have disappeared and are going to be robo
37. S01E37Bartleby the PrisonerOctober 19, 1999—Robotnik's new weapon, Art, is the enforcer of Robotropolis new eradication policy. Art's objective is to destroy everything in sight, inclu
38. S01E38The Art of DestructionOctober 20, 1999—Robotnik's new weapon, Art, is the enforcer of Robotropolis new eradication policy. Art's objective is to destroy everything in sight, inclu
39. S01E39The PendantOctober 21, 1999—The newly discovered Emerald Peninsula is a perfect place for Robotnik to add slaves to his empire. Sonic, Sonia and Manic are alerted of Ro
40. S01E40Virtual DangerOctober 22, 1999—Sonic and Manic play a game of virtual reality to enhance their pilot skills. When the two brothers decide to put their practice to use, the

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