Phantom Blood is a 3D beat'em up action game. Like GioGio's Bizarre Adventure, the gameplay takes place in the form of hand-to-hand battle in an arena the characters cannot leave, although unlike in GioGio multiple enemies can attack at once. The game is divided into chapters, in which the playable characters change for each chapter as the story progresses. After a fight, the game provides the player with a letter rank (S, A, B, C, D or E) based on a score of six categories: Time Taken, Health Remaining, Maximum Beat (Combo), Number of Times Downed, Posing and Enemies Defeated. Depending on the fight, the number of categories graded can range from three to six.
Stamina Meter and Poses
Characters capable of utilizing the Ripple show a Stamina Meter below their health meter. The Stamina Meter shows how much Ripple energy the character can use, and is depleted by performing Ripple moves ( by default) or charged attacks ( by default). Performing a counter by dodging while taking damage ( by default) also uses up the Stamina Meter. To refill the Stamina Meter, the player must remain still while performing a pose ( by default). Poses can also be used in the middle of combos to temporarily increase one of four different stats depending on where in the combo the pose is used: health recovery speed, defensive ability, attack power, and movement speed.
Overdrive
Above the character's health is a Heat Gauge, which fills up when damage is inflicted on enemies and lowers when the player takes damage. When the Heat Gauge is full, the words Heat MAX begin flashing inside of it, indicating that the player is able to use an Overdrive move ( by default). If the initial charge attack connects, the screen will change to a cinematic of the character preparing to attack over a multi-colored background. At a certain point, an empty bar will appear at the bottom of the screen; filling this bar by quickly rotating the right analog stick will cause the character to perform a barrage of attacks on the opponent, during which the player can tap the button to deal more damage. If the player doesn't fill up the bar, a less powerful attack will be delivered and inflict less damage. Only Ripple users and Speedwagon (Hammer) are able to use the Overdrive technique.
Story Mode
The story mode follows the manga history, step-by-step. The game is heavily composed of cutscenes faithfully re-creating the manga storyline through dialogue in static comic book cinematics, as well as fully 3D rendered cutscenes for key events. The cutscenes take up to 70% of the expected time to finish the game.
It's possible to win fights that the main character lost in the original storyline. If the player wins against the bullies or Dio in the boxing match, the following cutscene will be different. Losing these battles don't affect the gameplay in any way, prompting the player to normally continue story mode. If the player wants to retry a chapter, they can do so without needing to go through Story Mode again. By selecting Chapter Mode on the main menu, the player can freely play any previously beaten chapter.
Museum
Museum provides access to Profiles, with descriptions of almost every character met in the game, and Theater Mode, which allows the player to view all of the cutscenes seen in Story Mode. In addition, there are three sections that need to be unlocked:
- Extra Battle Mode: Play original scenarios that are not seen in the original story. This mode is unlocked by clearing Story Mode, and the battles themselves are unlocked by the player's total number of points.
- 77 Rings Knights Mode: Based on the trial of the 77 Rings, the player must battle 77 zombies in this survivor-like mode. The mode is split into two variations, Ripple Warriors and Living Corpses, which are unlocked by clearing Extra Battles 10 and 20 respectively.
- Dio Mode: Play through the game from Dio's perspective. Cutscenes are not present in this mode, and changes are made to the story to provide additional battles: for instance, Dio must battle Doobie and Adams together. This mode is unlocked by clearing Extra Battle 30.