How do you control characters in the game?

Slimerio is controlled with a mouse cursor or a finger on a touchscreen.

What is the objective of the game?

You must consume smaller slimes until you become the largest entity on the server.

What happens during a collision?

If an enemy is larger than you, the game ends, but if they are smaller, you consume them and grow.

Slimerio

IO Games12 playsUpdated: July 27, 2026

"Slimerio" is a browser-based io title where you control an amoeba and try to consume everyone smaller than you. Unlike most competitors, there is no speed boost or hidden power-ups, just pure size-based physics. The standout feature is the "law of the jungle" mechanic, where your avatar's size determines everything without exception.

Gameplay revolves around the endless race for biomass across a large map. You move the slime using your mouse or finger on the screen, steering it toward colored dots and small NPCs. Bumping into a larger opponent sends you straight to the menu, so always keep your distance. Every turn is a decision to risk it for growth or retreat to the arena's edge. The difficulty curve rises steadily: the larger you get, the harder it is to maneuver between giants.

Casual io fans will spend a lot of time here if they enjoy simple gameplay without complex upgrades. The title suits anyone looking to relax and drag a cursor around for ten to fifteen minutes. The gameplay doesn't require a long tutorial, but it doesn't forgive inattention.

Tip: play extra cautiously in the first minute, avoiding central clusters until you gain critical mass.

How to Play

Move your slime around the arena using your mouse or finger to consume smaller slimes and grow in size. Avoid larger slimes that can eat you.

FAQ

How do you control characters in the game?: Slimerio is controlled with a mouse cursor or a finger on a touchscreen.
What is the objective of the game?: You must consume smaller slimes until you become the largest entity on the server.
What happens during a collision?: If an enemy is larger than you, the game ends, but if they are smaller, you consume them and grow.