Deep Down in Darkness was going to be a first-person roguelike based on this 2.5D engine prototype. While this first attempt proved unworkable, the lessons learned were later applied to Electric Rogue. The user interface on the other hand was a success, soon reused in Glittering Light and other games since.
The game is designed for touchscreen devices, and scales within fairly generous limits, though it's best viewed in 800x480. With a keyboard, the arrow keys and WASD work, along with Escape, Space and Enter.
It was announced in Weekly Links #101, then never mentioned again until Weekly Links #167.