• Haunted Seas

What's old is new again, we've got a few reincarnations of old missions with a fresh new twist. It's almost as if your old favorites are coming back to haunt you!

The greatest common divisor Reborn from the famous Musical Module mission, The Greatest Common Divisor pits you against Euclid in a battle of mathematics!

Can You Jump Through? has evolved into the fantastic path-finding mission Can You Pass?

The classic Bullet and Wall mission has returned to us with the challenging Shooting Range!

We have 2 top secret missions for you this weekend. Be the first to earn the special "ghost mission" badge if you solve either of these missions...but play quickly because on Monday the missions will disappear like ghosts in the daylight!

The ghost missions are only available from Friday, August 29th 11AM GMT until Monday, September 1st at 11AM GMT.

A ghost ship has appeared nearby, but it's impossible to find through all this fog. Write an algorithm to detect it in the Ghost Detect mission.

Map out all of the safe zones where the Flying Dutchman cannot sail in Safe Coasts. Everyone is relying on you to navigate them to safety!

Become Awesome

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Welcome to CheckiO - games for coders where you can improve your codings skills.

The main idea behind these games is to give you the opportunity to learn by exchanging experience with the rest of the community. Every day we are trying to find interesting solutions for you to help you become a better coder.

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