Altered Beast (set 8, 8751 317-0078)
ARCADE

Altered Beast (set 8, 8751 317-0078)

Released in 1988 by legendary Japanese game publisher Sega, Altered Beast (set 8, 8751 317-0078) is one of the most iconic side-scrolling beat 'em up titles ever launched for arcade platforms. This specific ROM set is an unmodified, authentic early revision of the original arcade release, validated by the 317-0078 security chip to deliver the exact same gameplay experience players enjoyed in 1980s arcades. Set in a dark, mythic ancient Greece, the game casts you as a resurrected centurion summoned by Zeus himself to rescue his daughter Athena from the demonic lord Neff, who rules over the underworld. The core gameplay loop that made Altered Beast a global hit centers on collecting Spirit Balls dropped by special glowing white enemies scattered across each level. Collect three Spirit Balls, and you transform into a powerful mythical beast form, from a super-strong werewolf with piercing claw attacks, to a fire-breathing tiger, electricity-wielding dragon, petrifying bear, and the ultima

No download required
Save states supported
Works on mobile & desktop

The emulator loads after you press Start Game.

How to Play Altered Beast (set 8, 8751 317-0078)

Move
WASD
ABAction
JK
XYShoulder
L;
STStart/Select
21

Save & Load States

  • F2Press F2 to save your current game state at any time.
  • F4Press F4 to load your last saved state.
  • F3Use F3 to switch between save slots.

Save states are stored locally in your browser. They persist across sessions but are cleared if you clear browser data.

Customize Controls

Click the gear icon on the emulator toolbar → "Controls" to remap keys.

Move
WASD
Action
JK|L;
System
2 Start1 Select
Save
F2SaveF4LoadF3Slot

Default layout for ARCADE. Remap in emulator settings.

About Altered Beast (set 8, 8751 317-0078)

Altered Beast (set 8, 8751 317-0078) is a classic ARCADE game you can play online for free in your browser. No download or installation is required — click "Play Now" to start instantly. Relive the experience of vintage console gaming with authentic gameplay, right in your browser on any device.

This title is part of the PLAYERETRO game collection, which features over 1000 classic titles across multiple systems. Use the keyboard controls shown above to move and interact. Save your progress with save states and enjoy Altered Beast (set 8, 8751 317-0078) anytime, anywhere.

Play the authentic 1988 Sega Altered Beast (set 8, 8751 317-0078) ARCADE rom for free online on PLAYERETRO. Enjoy unmodified classic beat 'em up gameplay with full original arcade emulation.

Game Guide

Mastering Altered Beast (set 8, 8751 317-0078) is easy to learn but hard to perfect, starting with its simple three-button control scheme: punch, kick, and jump. First and foremost, prioritize targeting the glowing white enemy that spawns once per regular enemy wave at minimum: this is the only enemy that drops the Spirit Balls you need to unlock your beast transformation, and missing one will delay your power-up significantly, making boss fights far harder. While your base human form has weak, short-range attacks, you can use jump kicks to clear small groups of approaching zombies and ghouls safely while you wait for Spirit Balls to spawn. Once you transform, pick the right ability for each scenario: the werewolf form’s spinning dash punch covers a wide horizontal range, making it ideal for clearing packed groups of ground enemies in the first two levels. The dragon form’s continuous electric projectile attack is perfect for levels 3 and 4, where flying gargoyles and floating demon heads spawn in large numbers, as you can take them out from a safe distance without putting yourself in harm’s way. The bear form’s petrifying scream is extremely useful for the cave level, where fast-moving worm enemies spawn from all directions: freeze them first, then take them out with a single punch without taking damage. For boss fights, always make sure you have a full beast transformation before entering the boss arena: if you are still in human form when the boss spawns, take an extra 10 to 15 seconds to clear leftover minor enemies to grab the last Spirit Ball you need, rather than fighting the boss with weak base attacks. For the final boss Neff, wait for him to finish his charging slam attack, then hit him with 2 to 3 consecutive Golden Werewolf fire blasts before dodging his next attack, and you will defeat him in less than 30 seconds. This authentic set 8 ROM has consistent Spirit Ball spawn rates, so you never have to worry about missing a power-up due to glitchy programmi