Who made Altered Beast?

Altered Beast was published by SEGA, released in 1988.

What kind of game is Altered Beast?

Altered Beast is a action, platform, fighting game for the NES / Famicom.

Can two people play Altered Beast?

Yes. Altered Beast supports multiplayer (Multiplayer). Player 1 uses the arrow keys, player 2 uses WASD, and two USB or Bluetooth gamepads can be connected instead.

How much data does Altered Beast load?

The Altered Beast ROM is 109 kB. It is fetched once when you press play and then cached by your browser, so returning to the game does not download it again.

Which emulators can run Altered Beast?

Altered Beast runs on NES / Famicom and Nestopia UE (Accurate). You can switch between them from the emulator list further down this page if one performs better on your device.

Altered Beast Game (1988) - NES

Name: Altered Beast
Availability: InStock
Author: SEGA

Action / Button	Keyboard Key
D-Pad (Up / Down / Left / Right)	`Arrow Keys`
Button A	`Z` or `J`
Button B	`X` or `K`
Button X / Turbo A	`A` or `U`
Button Y / Turbo B	`S` or `I`
Select	`Shift`
Start	`Enter`

Gamepad Input	Retro Function	Keyboard Key
D-Pad / Analog	Character Movement / Steering	`▲` `▼` `◄` `►`
Button A (East)	Primary Action / Attack / Fire	`Z` / `K`
Button B (South)	Secondary / Jump / Cancel	`X` / `J`
Button X / Y	Special / Turbo / Extra Fire	`A` / `S`
Select	Insert Coin / Select Option	`Right Shift`
Start	Game Start / Pause Game	`Enter`

Gamepad Input

Retro Function

Keyboard Key

D-Pad / Analog

Character Movement / Steering

▲ ▼ ◄ ►

Button A (East)

Primary Action / Attack / Fire

Z / K

Button B (South)

Secondary / Jump / Cancel

X / J

Button X / Y

Special / Turbo / Extra Fire

A / S

Select

Insert Coin / Select Option

Right Shift

Start

Game Start / Pause Game

Enter

Emulator Core Engine	Technology	Multiplayer	Gamepad	Touch	Ads	Action / Switch
EmulatorJS (Default WebAssembly)	`WebAssembly / JS`	YES	YES	YES	NO	▶ ACTIVE
NES / Famicom (Recommended)	`WebAssembly / Libretro`	YES	YES	YES	NO	PLAY ⚡
Nestopia UE (Accurate)	`WebAssembly / Libretro`	YES	YES	YES	NO	PLAY ⚡

Emulator Core Engine

Technology

Multiplayer

Gamepad

Touch

Ads

Action / Switch

EmulatorJS (Default WebAssembly)

WebAssembly / JS

YES

▶ ACTIVE

NES / Famicom (Recommended)

WebAssembly / Libretro

YES

PLAY ⚡

Nestopia UE (Accurate)

WebAssembly / Libretro

YES

PLAY ⚡

Altered Beast is a 1988 side-scrolling action beat ’em up developed by Sega for arcades and ported to the NES. Set in Ancient Greece, players control a resurrected centurion summoned by Zeus to defeat the demon god Neff and rescue Athena. Defeating spirit wolves drops power orbs that mutate your hero through increasingly powerful beast transformations—including a Werewolf, Weredragon, and Werebear—each granting devastating melee and projectile attacks.

How to Play

Advance through each stage fighting monsters, collecting power orbs to upgrade your physique, and triggering beast transformations before facing Neff at the end of each round. Default browser controls mapped for Player 1:

Movement (D-Pad): Arrow keys (Up / Down / Left / Right)
Punch / Special Attack (A): X
Jump (B): Z
Start / Pause: Enter
Select: Shift

Tips

Prioritize White Wolves: Target the flashing white spirit wolves immediately when they appear, as collecting three spirit orbs per stage is required to transform into a beast before facing Neff.
Master Beast Mobility: Each transformation alters your movement and attack angles—for example, the Weredragon flies freely across the screen and shoots electrical projectiles, allowing you to attack bosses from safe distances.
Watch for Charging Foes: Basic enemies like zombies and head-throwers attack relentlessly; use high/low kicks or rapid punches while human to prevent getting cornered.