Mystic Cave Zone, an example of an underground-themed stage, from Sonic the Hedgehog 2.
The underground theme is a stage theme that appears in the Sonic the Hedgehog series. Stages with this theme take place in caves, generally beneath the surface.
Common elements seen in underground-themed stages are minecarts and gems. Most of these stages are also combined with fire, underwater and ancient ruins themes.
Stages with an underground theme[]
- Under Ground Zone, Sonic the Hedgehog 2 (8-bit) (1992)
- Mystic Cave Zone, Sonic the Hedgehog 2 (16-bit) (1992)
- Tidal Tempest, Sonic the Hedgehog CD (1993) - Mainly predominated in the past timeline; this round also incorporates elements of the ancient ruins and the underwater themes. Future timelines incorporates the industrial theme.
- Quartz Quadrant, Sonic the Hedgehog CD (1993) - The past incorporates underground element while present and bad future incorporates industrial elements and good future incorporates urban elements.
- Toxic Caves, Sonic Spinball (1993)
- Endless Mine, Sonic the Hedgehog 3 (1994)
- Hydrocity Zone, Sonic the Hedgehog 3 (1994) - This zone also incorporates elements of the ancient ruins and underwater themes.
- Toxic Pools, Sonic Spinball (8-bit) (1994)
- Lava Reef Zone, Sonic & Knuckles (1994) - This zone also incorporates elements of the fire theme.
- Hidden Palace Zone, Sonic & Knuckles (1994) - This zone also incorporates elements of the ancient ruins theme. Although sharing the same name from Sonic 2, it does not have an underwater theme.
- Mystic Cave, Sonic Drift 2 (1995)
- Quake Cave, Sonic Drift 2 (1995)
- Ruin Wood, Tails' Skypatrol (1995)
- Volcanic Tunnel, Tails Adventure (1995) - This stage also incorporates elements of the fire theme.
- Polly Mountain, Tails Adventure (1995)
- Cavern Island, Tails Adventure (1995) - This stage also incorporates elements of the underwater theme.
- Red Mountain, Sonic Adventure (1998) - This stage also incorporates elements of the canyon, fire, and sky themes.
- Aquatic Mine, Sonic Adventure 2 (2001) - This stage also incorporates elements of the underwater theme
- Mystic Mansion, Sonic Heroes (2003) - This stage also incorporates elements of the haunted theme.
- Terror Hall, Sonic Heroes (2003) - This stage also incorporates elements of the haunted theme.
- Gigan Rocks, Sonic Riders: Zero Gravity (2008) - This stage also incorporates elements of the ancient ruins, East Asian, and canyon themes.
- Hydrocity Zone, Sonic the Hedgehog (Didj) (2008) - This Zone also incorporates elements of the ancient ruins theme.
- Crystal Cave, Sonic and the Black Knight (2009)
- Knight's Passage, Sonic and the Black Knight (2009)
- Dragon's Lair, Sonic and the Black Knight (2009)
- White Park Zone, Sonic the Hedgehog 4: Episode II (2012) - This zone also incorporates elements of the amusement, winter and the underwater themes.
- Windy Hill, Sonic Lost World (Wii U) (2013) - Mainly predominates in Zone 3.
- Silent Forest, Sonic Lost World (Wii U) (2013) - Mainly predominates in Zone 3.
- Hidden Palace Zone, Sonic the Hedgehog 2 (2013) - Originally seen in the Simon Wai prototype. This zone also incorporates elements of the ancient ruins and underwater themes.
- Proto Palace Zone, Sonic the Hedgehog 2 (2013) - This zone also incorporates elements of the ancient ruins and underwater themes.
- Boss Attack Zone, Sonic the Hedgehog 2 (2013) - This zone also incorporates elements of the Green Hill, industrial, ancient ruins, underwater, urban, sky, fire and space themes.
- Crater Lake, Sonic Boom: Rise of Lyric (2014) - This stage also incorporates elements of the fire theme.
- Junction, Sonic Dash 2: Sonic Boom (2015) - Mainly predominates when the player switch the character.
- Fissure Tunnel, Sonic Boom: Fire & Ice (2016) - This stage also incorporates elements of the fire and winter themes.
- Paleo Tarpits, Sonic Boom: Fire & Ice (2016) - This stage also incorporates elements of the forest theme.
- Hydrocity Zone, Sonic Mania (2017) - This zone also incorporates elements of the ancient ruins and underwater themes.
- Lava Reef Zone, Sonic Mania (2017) - This Zone also incorporates elements of the fire theme.
- Hidden Volcano, Team Sonic Racing (2019) - This track also incorporates elements of the winter and fire themes.
- Frozen Base Zone. Sonic Superstars (2023) - This Zone also incorporates elements of the industrial, winter, sky and space themes.