A meta-JavaScript adventure game by Alex Nisnevich and Greg Shuflin.
Untrusted —or— the Continuing Adventures of Dr. Eval is an exciting Meta-Javascript Adventure Game wherein you guide the dashing, steadfast Dr. Eval through a mysterious MACHINE CONTINUUM, wherein, using only his trusty computer and the TURING-COMPLETE power of Javascript, he must literally ALTER HIS REALITY in order to find his freedom! You must literally edit and re-execute the very Javascript running the game in your browser to save Dr. Eval from this dark and confusing reality!
Overview
The game presents you with a roguelike-like playing environment and a console window with the JavaScript code generating each level. As loaded, each level is unbeatable, and most of the JavaScript is blocked from editing. The challenge is to open a path to the next level using only the limited tools left open to you.
Source: The Developer Website.