Dead Line (デッドライン Deddorain?) is the seventh Zone in Sonic Rush. It appears to be a space station built by Dr. Eggman. Like previous stations, such as the Death Egg, Dead Line is built in the shape of Eggman.
This zone has a feature seen in previous recurring levels set in outer space: the gravity will be reversed at various points of the stage although the player's controls will still remain normal. The zone also features gimmicks such as cannons and maneuverable rockets. There are also vacuums that suck up the player's rings if they were to get damaged near them. As such, they are usually placed near enemies and spikes where the player is likely to take damage. The purple Chaos Emerald and Sol Emerald are found here. The song for Dead Line is "What U Need."
When playing as Sonic, Special Generators appear throughout this Zone which can warp the player to the seventh Special Stage for a chance to collect the purple Chaos Emerald. As Blaze, the purple Sol Emerald can be found after defeating the boss.
After the fight, Blaze becomes friends with Sonic, but quickly discovers Cream was taken by Eggman during the battle and heads to the Unknown (also known as Point-W) to fight him and save Cream. In Sonic's story, he asks Blaze if she's okay and the two become fast friends after Sonic teaches her to open up and to not be so hard on herself. Sonic then rushes off to the Unknown (also known as F-Zone) in his story to fight Eggman Nega.
The boss of this zone features Sonic and Blaze fighting against each other. Depending on who the player controls, the fight will slightly differ between each character.
- This stage resembles Final Rush from Sonic Adventure 2 in that both levels take place in space and both have boss battles featuring Sonic fighting against his counterpart in their respective games (Shadow in Sonic Adventure 2).
- Act 2 has the most rings in a single stage in Sonic Rush as it is possible to get over 700 rings. This is also the only stage in the game in which the player can get 999 rings. (This does not include using Debug Mode in the classic games, or rings from bonus stages or warp rings in Sonic the Hedgehog 3 or Sonic & Knuckles).
- There is a glitch that may appear in the boss of this zone where the opponent does not make a move for a limited time after the start. This results in the player being able to hit the opponent 7 times quickly without being hurt in the process, yielding an easy S Rank.
- Act 1 of Dead Line can be accessed in the the Sonic Rush E3 Demo by swapping the files over. Leaf Storm Act 1 and Water Palace Act 1 also exist. Dead Line, however, was incredibly unfinished, and was impossible to complete. It is unclear why the demo has this alpha level, as others levels are from Stages 1 (Leaf Storm) and 2 (Water Palace) and everything between them and Dead Line is unavailable.