Underwater arena
Deeeep.io
Start as something small in the shallows and eat your way down to something that other players actively avoid.
- Made by
- Federico Mouse
- Released
- 2016
- Shelf
- The ride · 10–20 minutes
- One session
- Ten to twenty minutes per life
- Account
- Account optional
- Connection
- Live multiplayer: a dead spot ends the round
- Controls
- Mouse, or a touch pad on a phone
- Pays its way with
- Adverts; skins cost coins you earn
- Last retested
- 22 September 2026
Opens the developer's own site in a new tab. The link is editorial: nobody paid for it, and we get nothing if you click it.
- To start
- £0, nothing to install
- Most it will sell you
- Nothing we could find for real money
- Paid random items
- None
Every price, with its source: what each cabinet really costs.
The first five minutes
You are a fish. Everything is bigger than you. You eat plankton, fill a bar, and pick your next animal from a short list — and about four evolutions later you realise the shape gliding above you used to be somebody's starter fish too.
A food chain that teaches itself
The evolution list is the tutorial. Each creature has a habitat it is happy in, a thing it can eat and a thing that eats it, and you learn the whole ecosystem by being on the wrong end of it a few times.
Modes cover free-for-all, teams and one-against-one, and there is a public leaderboard on the front page for people who want a target.
What a session looks like
Ten to twenty minutes is the usual arc: small and cautious, then comfortable, then over-confident. It suits a ride across town, with the standard arena caveat that leaving mid-life throws away the animal you built.
Touch controls exist and work, but this is a game about small movements near obstacles, and a mouse gives you a precision a thumb does not.
Money, adverts and the chat channel
Skins are bought with coins earned by playing — score enough or land enough eliminations and the coin arrives. There is no real-money box to open, which is why it is here.
The site carries advertising with a long list of partners; decline the optional consent when the banner appears. There is also open chat between strangers, and we could not find a published moderation policy, so treat it as a public room: fine for most, worth knowing about before you hand it to a child.
What works
- Eighty-plus creatures give the arena a genuine progression to learn
- No account needed to start playing
- Skins are earned with in-game coins, not bought at random
- Works in a mobile browser as well as on a desktop
What grates
- Open chat with strangers and no published moderation policy
- Advert consent banner with a long partner list
- Leaving mid-life loses everything you evolved into
The verdict
The most characterful arena on the floor: an ecosystem rather than a scoreboard, and it earns its middle shelf. Marked down for the public chat and for how much a mid-ride exit costs you.
Questions we get asked
Is Deeeep.io free to play?
Yes, in the browser, paid for by advertising. Skins cost coins that you earn by playing.
Do I need an account?
No, you can start without one. An account keeps your progress and unlocked skins.
Is there chat?
Yes, between players in the arena. We found no published moderation policy, so treat it as a public space.