Fireflies

Each light drops down a channel that splits twice. Switch the junctions so it arrives at the exit that matches its shape and color. Every type differs in both shape and color, so you do not rely on color alone.

Point the junctions so each light reaches the exit that matches its shape and color. You lose after three lights go the wrong way.

Tips

Tap a junction to change its direction, or use the 1, 2, and 3 keys.
Use the arrow keys to choose a junction and Space to switch it.
Each type is told apart by its shape and color: circle, diamond, triangle, and square.
The lights fall faster and faster: make the switch before they reach the junction.

Step by step

How to use it

Select Play to start: every game has its own mix of lights and exits.
Tap a junction to change its direction, or use the 1, 2, and 3 keys.
Use the arrow keys to choose a junction, and Space or Enter to switch it.
Make each light reach the exit with the same shape and color. The game ends after three mistakes.

FAQ

Frequently asked questions

How do you play Fireflies?

The lights drop down a channel that splits twice before reaching four exits, each with its own shape and color. You change the direction of the junctions so each light ends up at the exit that matches its type.

How do I tell the types of light apart?

Each type is identified by its shape as well as its color: circle, diamond, triangle, and square. The exit shows the same shape and the same color, so you can play even if you have trouble telling colors apart.

When does the game end?

Every light that reaches the wrong exit counts as a mistake. After three mistakes, the game is over. The lights fall faster and closer together as you go, so you have to anticipate the switches.

Can I play on my phone?

Yes. Tap the junction you want to switch right on the screen. The play area does not scroll the page while you tap.

Is my best score saved?

Yes. When each game ends, your matches and your best score are saved in your browser’s local storage, along with a chart of your last games. Nothing is sent to a server.

How many types of light are there?

In each game, between two and four different types appear, spread across the four exits. Every game orders the lights differently, so there is plenty of variety.

How to play Fireflies

The lights appear at the top and drop down a channel. Halfway down, the channel splits in two, and further down each half splits again, leaving four exits at the bottom. At each junction there is a gate that decides whether the light continues to the left or to the right, and you can switch it whenever you like.

Shapes and colors

Each type of light has its own shape: circle, diamond, triangle, or square. The exit of the same type shows the same shape and the same color. Shape is the main signal, so the game does not depend on color alone and stays clear for everyone.

Strategy: look further down

Switch the gate before the light reaches it, not while it is already crossing.
With several lights in flight, deal with the lowest one first: it is the next to be decided.
Remember which half leads to each shape: the first junction picks the pair of exits, and the second picks the exact one.
Do not overcorrect: an extra switch can send another light off course when it was already on the right path.

Common mistakes

The classic slip is switching the gate just after the light has passed, so the change affects the next one. It also happens when you chain switches by reflex and divert lights that were fine. It is better to move only the gate you need and to watch where each light is relative to its junction.

Rising difficulty

With every match the lights fall a little faster and appear closer together, until several share the channel at once. The game ends after three mistakes, so the key is to stay calm and switch only when it is needed.

Updated on October 2, 2026