At the start of the game, the player is given three lives, each of which may be lost if Sonic collides with hazardous enemies or objects while in possession of no rings, falls to the bottom of the level screen, or exceeds an act's ten-minute time limit. Signposts act as checkpoints to allow Sonic to return to the most recently activated post when he loses a life. The time resets when he returns to the checkpoint. The game ends when the player runs out of lives, although the player may return to the beginning of the act with three lives if the player has any continues.