From TI-99/4A-Pedia
Jump to: navigation, search

Slymoids is an action/shooter video game distributed by Texas Instruments (TI) for the TI/99/4A home computer system. It was programmed by James R. Von Ehr II and converted for cartridge use by John Phillips and released during the first quarter of 1984 on Solid State SoftwareTM Command Module. It originally sold for $29.95 (USD).

Slymoids (Front Cover) [1] [2]
Publisher(s) Texas Instruments (TI)
Original Retail Price $29.95 (USD)
Programmer(s) James R. Von Ehr II converted for TI-99/4A by John Phillips
Part# PHM 3197
Format(s) Solid State SoftwareTM Command Module
Release 1984 (1st Quarter)
Genre(s) Action, Shooter


The player in Slymoids controls a cowboy tasked with fighting off the "Slymoids" armed with his trusty pistol. These creatures approach the player either from the horizon or from the sky. The player can shoot up at the Slymoids descending from the sky, or side to side at those approaching from the horizon. The player can control his/her cowboy moving either left or right in search of the enemies. The game takes place in three different locations: 1. in a city, 2. along the coast line, and 3. in a cavern. The player gets to choose from 4 different levels of difficulty to begin the game.

Advertising Blurbs

Front Cover of Manual

You are a sharp-shooting cowboy battling hordes of alien Slymoids. Attack them on grassy slopes, in castles, and in caves. Shoot quickly before the creatures overpower you!

Triton Catalog - Spring 1984

A 1-player arcade entertainment. Fiendishly clever alien Slymoids are attacking. You're a cowboy sharp-shooter - and you've got to be, to score hits with your Slymoid Scanner and Laser Fireballs! Chase through fields, castles and caves. 3-D effects and 5 levels of difficulty enhance the fun. (Wired Remote Controllers recommended.)

Fun Facts

  • Texas Instruments was concerned that the theme music that James Von Ehr II created for the game was actually stolen from another source. He had actually created it years earlier on his home-built analog synthesizer controlled by his Apple II computer. [3]
  • Programmer James Von Ehr II placed a couple of Easter Eggs in Slymoids. Inside of the castle around the swords that hang on the wall can be seen the initials JVONEHR and GVONEHR James and his wife's (Gayla) initials. Gayla is credited by James as having offered helpful design suggestions for the game. [4]



In this one-player game, you are a sharp-shooting cowboy-the last defense against the hordes of alien Slymoids. Use your Slymoid Scanner and Laser Fireball Weapon to locate and destroy these strange life forms. The devious Slymoids also appear in two other forms-Jelloids and Spores. Chase the Slymoids through fields, castles, and caves. But beware! The crafty Slymoids have turned spiders, bats, and even rocks against you.

With Slymoids you can:

  • Experience multi-screen graphics
  • Enjoy graphics that create a 3-D effect
  • Choose from 5 levels of difficulty
  • Use Wired Remote Controllers (joysticks) or keyboard control
  • Hear special sounds that warn you a creature is about to appear

Playing the Game

When the game begins, you are located in one of three battlefields: a grassy slope, a castle, or a cave. You can destroy some creatures with a single shot. Other creatures must be shot several times before they are eliminated. As each battlefield is cleared of Slymoids, you move to another location. If you are victorious, you progress to the next level of difficulty. Destroy all the Slymoids before they overcome your cowboys.

Special Keys

Key Function
AID Goes to demonstration game.
REDO or BACK Returns to the title screen BACK from the demonstration game.
SPACE BAR or P Pauses during the game. Press any key to resume play.

Selecting Playing Levels and Locations

The numbers 1-5 on the title screen represent the levels of play (1 is the easiest level; 5 is the hardest). An asterisk moves under the levels of play.

To choose a level of play, press any key ( other than the number keys) when the asterisk is under the level of play you desire.

There are also four battle locations in the game. Location 1 is a grassy slope. Location 2 is inside a castle. Location 3 is a grassy slope. Location 4 is inside a cave.

When the asterisk appears under the level of play you desire, press 1, 2, 3, or 4 to choose a specific location.

Reserve Cowboys

In addition to the character on the screen, you have 3 cowboys in reserve at the beginning of the game.

When a cowboy bites the dust, he is automatically replaced by one of the remaining cowboys.

When you eliminate all the creatures from one location, the screen goes black. Then, a new location appears and you receive an additional reserve cowboy.

Scanning for Creatures

A special Slymoid Scanner is shown in the lower left-hand corner of the screen. The arrow indicates your location, and the colors change as more creatures appear on the screen.

0 to 10 Creatures

  • Dark Green
  • Light Green
  • Yellow

More than 10 Creatures

  • Light Red
  • Dark Red
  • Black

Moving the Cowboy Using Wired Remote Controllers

To move the cowboy, push the lever of the Wired Remote Controller Joystick) to the left or right.

Shooting Creatures Using Wired Remote Controllers

To shoot the creatures, aim the cowboy's laser gun in the direction you wish to fire and press the FIRE button. Aim is controlled with the following joystick movements.

Lever Position Direction on the screen
Forward (toward the FIRE button) Toward horizon
Backward (away from the FIRE button) Toward sky
Left Left
Right Right

Note: The ALPHA LOCK must be in the OFF (up) position when using the Wired Remote Controllers.

Moving the Cowboy Using the Keyboard

To move the cowboy, press the (←) S and (→) D keys.

Shooting Creatures Using the Keyboard

To shoot the creatures, aim the cowboy's laser gun in the direction you wish to fire and press the period key(.), ENTER, Q, V, or Y. Aim is controlled with the following keys.

Keys Direction on the screen
(↑)E, (↑)I Toward horizon
(↓)X, (↓)M Toward sky
(←)S, (←)J Left
(→)D, (→)K Right

Ending the Game

The game ends when you destroy all the Slymoids, or when the Slymoids overcome all of your cowboys.

To play the game again using different options, press BACK or REDO.

Preparing for More Action

As you play Slymoids, you discover strategies to help you become a better player. As you become more skilled, you advance to more difficult and more challenging levels of play. With practice, soon you can be a local hero.


Your score is automatically calculated and appears on the screen. You receive points according to the type of Slymoid you hit and where it is located when you destroy it. The more difficult the shot, the more points you receive.

Points Type Shooting Direction
10 Any hit Bottom line of screen, left or right
25 Slow Jelloids Up
50 Slymoids Into horizon
50 Medium Slymoids UP
50 Spores Up
50 Falling Rocks Up
75 Fast Jelloids Up
75 Spider Up
75 Spores (flying at an angle) Up
125 Bat Into horizon

Playing Tips


  • Shoot the Slymoids before they multiply
  • Watch the Scanner and plan your moves based on the number of Slymoids in the area
  • Listen for the unique sounds of each creature as an early warning of an attack
  • Prepare to retreat if in danger


  • If spores escape off the screen or land on the ground before being destroyed, they change into three new Slymoids
  • If three Slymoids come together in the same immediate area, they generate a new Slymoid
  • Cave rocks may come to life and attack you if Slymoids are near them
  • Spiders and bats are allies of the Slymoids and are your enemies



External Links