Hydra Slayer is a Roguelike game focused on one thing: slaying Hydras. It is inspired by mathematical puzzles about brave heroes slaying many-headed beasts. Since each weapon can only cut off a specific number of heads (no more, no less), and then the Hydra regrows some of the lost heads, to defeat each Hydra, you need to find the sequence of attacks which kills it in the least number of wounds. Hydra Slayer also features divisor weapons, blunt weapons to stun heads, missiles, and shields, and a number of other magical items which are unique to this game.
Blacken is a Java library for Roguelike development. It supports arbitrarily resizing the window. It maintains a "preferred size", changing the font size as needed. By default, all applications support Alt-Enter for fullscreen mode. It strives to support Unicode well. A cell contains a sequence of codepoints. Codepoints may be outside the Basic Multilingual Plane or zero-width accents. All key input consists of valid Unicode codepoints. Special keys are handled by codepoints in "private use" planes. Modifier keys are handled through a prefix character (like Unix systems handle Alt via the Escape character).