The Sub-Character is a power-up that appears in Sonic Runners. When used, the player will swap a character.
The Sub-Character's icon takes the appearance of the top section of a smiling and red humanoid figure with a blue and orange arrow circling around it.
The Sub-Character appears as a Booster Item in Sonic Runners. It can be selected before a run, at the cost of 4.000 Rings. In gameplay, the Sub-Character allows the player to swap their main playable character with a sub-character during a run through the stages. However, when used, the Items the playable character is currently using will wear off.
If one of the player's characters fails a run, the Sub-Character will be used automatically to allow the player to continue playing with the other character. When this happens, the player will not be able to use the Sub-Character unless both characters die and the run is continued by paying Red Star Rings.