Venture Forth Blueprints allow you to not only customize your levels, but to build an entire game from scratch using Arclight Worlds' custom engine. Jeremy Ingham's very easy to understand building language is easy to learn and contains very simple but powerful commands that'll enable you to not only build incredible worlds of your very own, but now you can blueprint your very own equipment and critters.
Check out my tutorial in the Guides section to get a running start. New versions of the guide coming out this weekend.
- indievoyagerob