Altered Beast

Altered Beast is a 1988 arcade video game developed by Sega R&D1 and released by Sega Enterprises Inc. in the USA on June 30, 1988.

The game's premise is that Neff, ruler of the underworld, captures the goddess Athena. Her angered father, the Olympian god Zeus, decides to choose a champion to save her. Respecting the bravery of Roman Centurions, Zeus resurrects one of them and empowers him as a champion. The player character is the resurrected Roman Centurion, given extra power by Zeus so he can battle Neff and his supernatural minions. Whenever the player defeats a white two-headed wolf, a Spirit Ball power-up appears. Each obtained Spirit Ball increases the player character's strength and size. Collecting three Spirit Balls allows the player character to transform into a powerful beast form, increasing their combat abilities before having to face Neff at the end of the level. The player character's beast forms include a weredragon, a werebear, a weretiger, a werewolf, or a golden werewolf. Each beast form grants its own abilities. The dragon can unleash lightning bolts and an electric barrier, the bear has a petrifying breath that turns enemies into stone, the tiger can hurl fireballs in a zigzag pattern, the wolf can throw direct, but weak fireballs and has a powerful thrust attack, while the golden werewolf has the same abilities as the wolf form.

Source: TheGamesDB