Red Slime

Red Slime, sometimes known as Red Liquid or Conduit Gel, is an gimmick used in the video game Shadow the Hedgehog. The Red Slime is the main transport system inside the Black Comet and other Black Arms colonies. It primarily exists only within the Black Arms-colonies.

Description
The Red Slime is a red liquid made to look like a vine of some sort. The primary transport for the Black Arms species, any creature that is kin to the Black Arms can potentially insert themselves inside the Red Slime and slither through wherever the Red Slime puddle, which marks the end of the slime, is located. In the video game Shadow the Hedgehog, the player, who controls Shadow the Hedgehog can use the Red Slime to transport throughout the levels. Almost every level in Shadow the Hedgehog has a Red Slime link via Spin Dash. It actually is not explained whether the Black Arms could use the Red Slime themselves in Shadow the Hedgehog.

Archie Comics
The Red Slime gimmick has reappeared in the Sonic the Hedgehog comic series and its spin-off comics published by Archie Comics. In Sonic Universe #59, the Red Slime appears inside the New Black Comet, where it serves the exact same function as it does within Shadow the Hedgehog. It should be noted that the Red Slime in the Archie Comics was refereed to as the "Conduit Gel".

The Red Slime appeared inside the New Black Comet when Team Dark–Shadow, Rouge the Bat, and E-123 Omega–along with the Spider Troupe reached a dead-end. Shadow felt the Red Slime and sensed that he could potentially warped himself inside to enter another section of the New Black Comet. Rouge stated that this was a bad idea, considering no of them knew what was up ahead. Regardless, Shadow spin dashes himself in the Red Slime, only to come inside a room filled with Black Arm soldiers. (SU #59)