Shadow the Hedgehog is a platform game that incorporates elements of action-adventure gameplay. Like previous games in the Sonic series, basic gameplay involves running quickly, collecting rings, and destroying enemies. Shadow collects rings as a form of health; when he is attacked by an enemy, ten of his rings bounce away from him in all directions. If he is hit by an enemy while not having any rings, he loses a life. Each level is completed by undertaking a mission, and each mission is labeled "Hero," "Dark," or "Normal." The "Hero" missions involve completing tasks for the Sonic series' heroic characters, or Doctor Eggman on one occasion, and the "Dark" missions involve completing tasks for the Black Arms or Doctor Eggman. The "Normal" missions involve reaching the Chaos Emerald or goal at the end of the level. All enemies attack Shadow regardless of the mission chosen. The mission types selected affect the plot, the levels played, and the ending received out of ten possibilities. Each level features cutscenes that advance the story, and several levels also feature boss battles.