Beamhold

Beamhold is a strategy puzzle about light and shadow. The invaders are shadows that will not walk in light: each one walks, cell by cell, along the cheapest road from a dark rift to the keep's gate, and every lit cell costs it dearly. A crystal casts one beam. Bend it with mirrors, fork it with a splitter and set lanterns, and the light becomes living walls that steer the shadows onto the longest dark road you can build. Every night has a clock: at dawn every shadow still on the field melts away, and only those that reach the gate cost lives. The beam fades with distance and at every mirror, so if light closes every road the shadows cross where it is faintest, and light burns whatever stands in it. A dotted line always shows the road the next shadow will take, and a gold one the road a piece under your cursor would make. Four fields of eight nights each, with quick wisps, heavy husks that push through faint light, and the Long Night at the end of every field. It plays in the browser with a keyboard, mouse, touch or gamepad, in English and Bulgarian.