C-40 contest games


The C-40 contest was held in 2007. The challenge was to create a Z-code game in 40K or less. Z-code is normally used to create interactive fiction, but any type of game was allowed in this contest. These three games were the only entries.

You will need an interpreter to play these games, such as Windows Frotz.


A real time racing game with thirty one levels, four modes, a customisable interface and a level editor.

You can download it here.

(Note that not all interpreters handle timed events properly – the title screen should be animated).

ZRacer screenshot

ZRacer Help

This game consists of 30 different tracks and a bonus level. The aim is to complete each track in under a certain time. Once you have completed a track, other modes of play become available for that level, and the next level is unlocked.

To complete a track, you must return to the starting point three times, and collect all three pickups.

You have a limited amount of fuel during the game. If you run out, your maximum speed is reduced. Collect fuel tokens to restore your fuel level to 100%. You can increase or decrease your speed with the space and B (brake) keys, and turn using the arrow keys.

Some corners have a speed limit. If you are going just above the limit, your speed is automatically reduced. If you are going any faster, you crash into the side of the track and lose some time.

When a level is completed, other modes of play are unlocked The normal mode is called Laps. The other modes are:

Time Stop -- get as many pickups as you can. Pickups extend the remaining time.
Count Down -- pickups count down from 9 to 0, then disappear. Grab them first.
Search -- find the pickups on a partly invisible track.

Racing Tips

Level 31 (unlockable)

This level is quite different to the other levels; you can learn a lot by experimenting. There is no fixed track, and you can exit one side of the arena and come back in the opposite side.

Avoid bumping into the diamonds and pay attention to the compass direction at the bottom right. You'll soon get used to the changes!


A logic game with four difficulty levels, inspired by an old puzzle called “my very eccentric aunt.”

You can download it here.

Animals screenshot

Animals Help

Animals is a game of logic. The aim is to deduce the rules that are used to classify words as “in” or “out” of a group. The words are all animal names, but the animals themselves are not important; the letters are what matters.

You win by collecting the required number of blue tokens. In levels two to four, there are other colours as well; to win in these levels, you also need to end up without any non-blue tokens. There is always a way to do this.

You are presented with one or more groups of animal names (one group for each level number). The words in each group have something in common; for example, they might all contain a “Q” or have the same number of vowels (note that “Y” is treated as a consonant). An animal may belong to more than one group.

There is also a long list of animals to choose from. Use Space to go forwards and “B” or “-” to go backwards through the list, and Enter to select an animal.

If the animal does not belong to any of the groups, you lose a point, unless the game decides that you didn’t have enough information. You lose the game after getting twelve animals incorrect.

If the animal does belong to a group, it is added to that group’s list, and the “effect” of that group happens. Effects include gaining tokens, losing tokens, and changing them from one colour to another.

Nothing happens if the effect is not currently possible (for example, changing red to blue if you currently have no red). In levels three and four, the effects are initially unknown, and are displayed as “(?...)”.

If the animal belongs to more than one group and only one effect is currently possible, it is performed automatically; otherwise you are given a list of effects to choose from.


A code breaking game with three difficulty levels. There are 73 different texts to choose from, all related to interactive fiction in some way.

Download it from here.

Cryptographer screenshot

Cryptographer Help

This game consists of a set of texts related to Interactive Fiction with the letters A-Z randomly reassigned; for example, “A” might stand for “C”, “B” might stand for “R”, and so on.

To decode a piece of text, press a letter key, then press the letter you think it stands for. To clear a letter and make it display the initial “-” value again, press Enter. If you press a letter by mistake and need to cancel it, press Space.

There should be enough information available to work out each code (it helps if you are familiar with Interactive Fiction) -- but if you do get stuck or impatient, you can find out the value of a letter by pressing (5), or you can see the whole solution by pressing (6).

To choose a different piece of text, press (2) and enter a number. If you press (2) by mistake, just press Enter to cancel.

You can change the game difficulty by pressing (7). In “Easy” mode, all punctuation and capitalisation is visible. In “Medium” mode, all letters are lower case. In “Hard” mode, there is no punctuation at all.

You can also input your own message for someone else to try decoding by pressing (8). This will be referred to as “text #0” by the game. Good luck!


Questions or comments to: davidfisher@australiaonline.net.au