Altered Beast

Altered Beast (獣王記) is a 1988 beat 'em up arcade game developed and manufactured by Sega. The game is set in Ancient Greece, and follows a centurion who is resurrected by Zeus to rescue his daughter Athena. To do so, he gains the ability to turn into beasts such as the werewolf through the use of power-ups.

Altered Beast is a side scrolling beat 'em up game with light platform elements. The player can punch, kick and jump. Up to two players can play at once. Each player controls a centurion, fighting undead creatures and monsters in a setting resembling Ancient Greece. One of the enemies, a white two-headed wolf which upon defeat releases a Spirit Ball, a power-up orb which increases the strength and size of the player. Three orbs turn the centurion into a different beast each stage. Each beast has its own abilities, such as the dragon's flight and lightning, and the bear's petrification.

After becoming the beast, the character can face the end-level boss, though the boss will also appear regardless of whether or not the character is transformed if the player takes too long to complete the level. Upon the boss's defeat, Neff appears and removes the transformation orbs. After its initial arcade release, it was ported to several home video game consoles and home computers, including the Mega Drive/Genesis, for which it was a pack-in game.

Story
A Greek Warrior who had died in battle is resurrected from the dead by Zeus. The Warrior is ordered by Zeus to save his daughter Athena from a Demon God called Neff in the Underworld. To become able to withstand the perils, the warrior is given the ability to collect three spirit balls on each level, the last of which transforms him into a human/beast hybrid of formidable power.