Firefly Jar

About Firefly Jar

Firefly Jar is a free online Simulation game that runs right in your browser. There is nothing to download and no account to create: press Play and you are in. It works on desktop, laptop, tablet and mobile.

A cozy incremental made of summer nights. Sweep the jar, which follows your mouse or finger, through the fireflies as fast as you like. Carry a full jar to the lantern before dawn takes it, and spend the light on a skill tree that is a real tree of hanging lanterns. Turning the season is the prestige: the crown goes dark, the roots keep tree rings, and every season brings something new to do instead of a bigger number. Will-o'-wisp trails lay paths home across the autumn moor, icicles split the light into coloured beams and an aurora dips into the winter meadow, spring buds keep light and pay it back with interest, and Midsummer grows the meadow into a forest until the fireflies rise into the Milky Way. Along the way a field journal fills with the real species you learn to tell by their light: glow-worms in the grass, the steady blue ghost, the synchronous fireflies of the Smoky Mountains that flash in bursts all together, and the femme fatale that fakes other species' signals to eat them. Every night has its own sky: puddles after rain that double what flies over them, wind that herds the fireflies to one edge, fog, a storm far off whose lightning the fireflies answer, and a moon that waxes and wanes, with a forecast after each night. At the end the lantern tree goes up into the sky as a constellation, and another year starts brighter. The meadow, the trees, the frogs and owls and thunder and the soundtrack are all made in code, with a tune of its own for each season: electric piano and guitar in summer, a harp waltz in autumn, a music box in winter and a flute in spring. About two hours from the first jar to the credits; progress is saved in the browser.

How to play

Press the Play button to load the game. Most games are played with the mouse or by tapping the screen; keyboard games use the arrow keys, WASD or the space bar. Read the in-game instructions for the exact controls, and use the fullscreen button for the best experience.

Frequently asked questions