DiGiT's compressor/decompressor programs for scenario (.scn/.scx) files. It can decompress your scn's into readable .hex file format. After you're done making the changes for the desired effect, use the compressor to compress the .hex file back to a scenario again.
You'll need a Hex Editor program like Cygnus or EditPadPro to open the .hex file, which you can then edit to your exact liking.
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A few examples of what can be done using these files:
- Total control of units/objects, terrain tiles, elevation and map size
- Access to the Lengthen Combat Mode/Triple Hitpoint mode
- Access to the Unknown civilization
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Custom Map Size Tutorial:
This tutorial by scenario_t_c/Trisolo covers everything you need to get started.
Only works with AoE. The 'Unknown Civilization' allows control of Gaia nature objects such as animals, trees, berry bush - all available as Player units.