RLX is a next-generation tile-based roguelike game engine library written in Common Lisp.
RLX supports tile-based 2.5-D worlds with a limited z-axis and interacting, independent agents called "actors". These actors are written with the help of a library called CLON (Common Lisp Object Network) which adds prototype-oriented objects to Common Lisp with a custom syntax. Both turn-based and pseudo-realtime play (i.e. a simple timeout) are supported.
RLX uses LISPBUILDER-SDL for cross-platform graphics and audio; the example game "Blast Tactics" works on GNU/Linux, Mac OSX, and Windows so far. (Precompiled binaries are not yet available for all platforms.) Other features include basic random terrain generation tools, simple AI support, GUI widget set with flexible keybinding system, ray-casting based light and shadow effects, Bresenham's LOS (line-of-sight) implementation.
Features in the process of being ported from an older Emacs Lisp implementation include A-star pathfinding, rule-based map generation, map editor, and a menu system.