How to play Gelz.io

Everything below is measured from the game's own configuration, so the numbers are what the server actually runs — not rounded guesses.

Gelz.io is a real-time multiplayer cell game. You steer a blob around a 20,000 by 20,000 pixel world, swallow the pellets scattered across it, and try to eat other players before they eat you. There is no round timer and no win screen: a run lasts exactly as long as you keep something alive, and it ends the moment your last cell goes down someone else's throat.

The first sixty seconds

Your cell follows your mouse. It never stops — there is no key to stand still, only a direction to travel in, so the cursor is a steering wheel rather than a destination. Drive over the little coloured pellets and you grow.

Growing costs you speed. Movement follows the cell's mass on a curve, and in the Megasplit world that curve means doubling your size leaves you roughly 14 % slower. A freshly spawned cell darts around; a 50,000-mass monster wallows. That trade is the whole game: everything smaller than you can run away, and everything faster is deciding whether you are worth the trouble.

Eating another player

You cannot eat someone just by touching them. Two conditions have to be met at once:

• you must be at least 25 % heavier than the cell you are swallowing, and
• your edge must cover a third of the way past their centre — a graze does nothing.

Splitting

Tapping Space cuts every eligible cell you own in half and fires the new pieces at your cursor. It is how you close distance — a split piece travels much faster than you can walk — and it is how you eat someone who would otherwise outrun you.

In Megasplit 128x, the world that is currently open, you spawn at 5,000 mass and can reach up to 128 cells. A cell needs at least 24 mass to divide, so there is a floor past which splitting stops.

Splitting is a commitment, not a free move. Every piece you throw out is a piece that has to come home again, and until it does you are a scatter of small cells that anyone bigger can pick off one at a time.

Getting back together

Split cells refuse to merge for a while. The wait is 30 seconds plus a fiftieth of a second per point of mass, so a 5,000-mass piece needs about two and a half minutes before it will recombine. Heavier pieces wait longer — which is exactly why splitting on top of a big player and missing is so punishing.

Multi-splits

Doing it by hand is slow, so two extra keys are bound out of the box: A splits twice in a row (one cell becomes four) and D splits as far as the cell limit allows. There are also unbound actions for 8, 16, 32 and 64 pieces if you would rather have that precision — put them on keys under Settings → Controls → Keyboard, or on your mouse buttons under Settings → Controls → Mouse.

Feeding

Holding W spits out a stream of 14-mass pellets toward your cursor. You need at least 24 mass to do it, and in Megasplit an ejected pellet that nobody eats disappears after five seconds.

Feeding is not just charity. It is how you pass mass to a teammate who is about to make a play, and it is how you weaponise viruses.

Viruses

The green spiky cells are viruses. They sit at 130 mass and they punish anyone careless enough to swallow one.

Run into a virus while you are small and it barely matters. Run into one while you are above 800 mass and you keep half of yourself as a core, then shed a cascade of halving chunks — a quarter, an eighth, and so on — with the remainder bursting into confetti. A big cell that eats a virus in the open is usually dead within seconds, because everything nearby is now bigger than each of your pieces.

Dual cells

Megasplit 128x is a dual world: you do not control one cell, you control two, spawned side by side and living independent lives. Press Tab to hand the mouse to the other one.

The half you are not steering does not freeze. It keeps travelling toward the point your cursor was on when you switched away, then settles there. Used well this is an enormous advantage: park one half somewhere useful, go hunting with the other, and switch back the instant something walks into your trap. Used badly it is two cells feeding two different players.

Freeze and the line split

Pressing S pins the world point your cursor was on. Your cells walk to it and park there, ignoring the mouse until you press S again.

On its own that is a handy way to hold position. Its real purpose is the line split. Freeze while aiming in a direction, then split repeatedly: every piece fires along the bearing captured at the moment you froze, so instead of a messy cloud you get a straight chain of cells stretching out along one line. Moving the mouse afterwards cannot bend it.

A line reaches far further than a single split, which makes it the tool for hitting someone across a gap they thought was safe. Once the chain has fully extended the freeze releases itself and the cells gather back toward the middle of the swarm on their own.

Why you cannot just grow forever

Above 200 mass you lose 0.6 % of your mass every second. It is gentle at first and brutal later: at 50,000 mass that is 300 points a second draining away. A cell that stops eating starts melting, so parking in a corner to protect a big score does not work. On top of that, any single cell reaching 100,000 mass in Megasplit breaks itself in two automatically.

Reading the map

The world is divided into a five-by-five lettered grid, A1 through E5, drawn faintly in the background and mirrored on the minimap in the corner. Those labels are what you use to call out positions in chat. B toggles the grid if you find it distracting.

You do not see the whole map. Everything beyond your view range simply is not sent to your browser, so zooming out reveals more empty ground rather than more players. Someone can be two sectors away and completely invisible to you.

Controls

Every one of these can be rebound under Settings → Controls, and the three mouse buttons can be given the same actions under the Mouse tab there.

Teams

Type up to four characters in the Tag box before you play and anyone using the same tag counts as your team. Teammates show up on your minimap wherever they are on the map, their skins stay visible to you while everyone else is drawn as a plain blob, and you get a private party channel in chat.

Signing in

The game is completely playable without an account. Signing in with Discord adds four things: skins, a level that grows with the scores you post, coins, and the ability to write in chat. Chat is limited to signed-in accounts on purpose — an anonymous troll is back under a new name a second after being removed, so tying it to an account is what makes moderation mean anything.

The monthly leaderboard

The menu lists the best runs of the current month, and it resets on the first. What counts is your best single run, not the total you have piled up — one enormous game beats a hundred mediocre ones. The score is the peak mass the server itself measured, and it is recorded whether your run ends by being eaten or by walking back to the menu.

Bodies left behind

When a player disconnects mid-game their cells do not vanish. They turn grey, are relabelled DEAD, stop moving, and sit there for eight seconds before despawning. Free mass, if you are close enough and big enough to take it.

Five things that will make you better

1. Stop splitting at everything. Most deaths are self-inflicted: you split at someone who was never catchable, and spent the next two minutes as bite-sized pieces.
2. Watch the edges. The world border cannot be crossed, so a player pushed into a corner has nowhere left to run. It is the easiest place to finish a chase.
3. Learn where the viruses are before you get big. Once you are over 800 mass they stop being scenery and become the thing most likely to kill you.
4. Keep eating. Decay never sleeps. If you are not gaining, you are losing.
5. Use both halves. In dual worlds, players who leave one cell idling in a corner are effectively playing at half strength against people who are not.