A downloadable game

BEYOND THE DOOR (10 liner) is a game written in ugBASIC and that runs on various 8-bit home computers like ATARI 400/800, COMMODORE 64, TRS-80 COLOR COMPUTER 1/2/3, AMSTRAD CPC 664, MSX and ZX Spectrum 48K/128K/+2.

The aim of the game is to exit from a maze, choosing the right door and avoiding the monster that chase you. You have a limited time to choose, and to explore the various doors. It is a self-competiting game, and it is designed for one player.

Click here to read the instructions on how to play.

This game joins the "BASIC10Liner" competition 2025.

Since it joined this competition, the game itself is modest in size, and the given source code respects strong constraints on the length of each line (category: EXTREME-256) and it does not rely on third party libraries.

The source code is available on this repository.

HOW MUCH HAS ugBASIC HELPED?

This cross-platform game would not have been possible without using ugBASIC: it is an isomorphic language and it has cross compilers that works on Linux and Windows, that directly converts high level algorithms into the assembly equivalent for the given CPU / computer.

Developing for multiple platforms requires very little effort because the source does not have to be adapted or, like this case, it can be adapted limited to the hardware dependent aspects. With a single source code you can obtain programs for multiple retro computers, even very different from each other. Moreover, each target can have a dedicated optimizer, which allows to achieve very interesting results while leaving the BASIC code fully readable.

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