Fish.io
Swim through a side-view ocean, gulp down smaller fish and plankton, dash away from bigger predators and grow large enough to survive the twilight and midnight depths.
Fish.io is an underwater eat-and-grow .io game seen from the side, from the sunlit surface down to a pitch-dark seabed. You start as a small fish nibbling plankton, then work up to darting schools of tiny fish and finally the named rival fish that share the reef. Anything noticeably smaller than you is a meal, marked with a green ring; anything noticeably bigger is marked red and will swallow you in one bite.
The ocean is split into three depth zones. The Sunlit Shallows are safe but thin on food, the Twilight Zone offers juicy shrimp, and the Midnight Deep holds glowing prey but is so dark you only see what your own light reaches. Each deeper zone needs a minimum size, and smaller fish lose mass to the pressure until they swim back up. Drifting jellyfish sting and stun small fish, oysters on the seabed hold pearls that trigger a feeding frenzy, and a quick dash helps you catch prey or escape. Eighteen computer fish chase, flee and grow alongside you, and big fish slowly lose mass, so staying on top takes steady hunting. Finish the four-minute round as the biggest fish to win.
Runs earn XP toward a saved rank that unlocks fish colours and perks like a bigger start, a faster dash and a brighter deep-sea light. Tip: chase schools in the shallows first.
How to play
Swim around to eat plankton, small fish schools and any rival fish with a green ring. Avoid fish with a red ring, which can eat you, and dodge stinging jellyfish. Dash to catch prey or escape. Deeper zones have richer food but require a minimum mass. If you are eaten the run ends; after four minutes, the largest fish wins. Your score is your peak mass plus a placement bonus.
Controls
- Mouse: Swim toward the pointer
- WASD / Arrow keys: Swim
- Click / Space / Shift: Dash
- Touch: drag left side: Virtual stick to swim
- Touch: DASH button: Dash
- Left / Right (title): Pick a skin
- P / Esc: Pause
- M: Mute
- R: Restart after a round
Category: .io games
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