Devlog

How the Daily Challenge Works (and Why Everyone Gets the Same Run)

October 10, 2026

Update, October 13, 2026: the Daily Challenge is switched off on this website for now. The Android apps still have it, and it will come back here.

All six games have a Daily Challenge button. Press it and you get a run that's identical for every player in the world that day: the same threats, in the same order, from the same directions. Tomorrow it changes. This post explains how that works and why it's built the way it is.

Update, October 13, 2026: PHASE.IO launched with a Daily Challenge too, so all seven games now have one.

GROUND.IO menu screen
GROUND.IO
INK.IO menu screen
INK.IO
PHASE.IO menu screen
PHASE.IO

Every game's menu has a Daily Challenge button right under Play.

Random, but repeatable

Games need randomness, or every run would be the same. But computers don't produce true randomness on their own. They use a pseudo-random number generator: a formula that takes a starting number, called a seed, and produces a long sequence of numbers that look random. The key property is that the same seed always produces the same sequence.

In a normal run, the seed comes from something unpredictable, so every run is different. In a Daily Challenge, the seed comes from the date.

Turning a date into a seed

The seed is built from the year and the day of the year. October 10, 2026 is day 283 of 2026, so the seed is a number built from 2026 and 283. Every player whose calendar says October 10 gets the same number, and so the same run. The date comes from your own device's local time, which means the daily changes at your midnight, not at a global one.

One subtle detail: only the parts of the game that decide what happens use the seeded generator. What spawns, where it spawns, how fast it moves. Purely visual things like particle sparks and screen shake use a separate, unseeded generator. That keeps the seeded sequence stable. If a cosmetic effect pulled a number from the same sequence, two players who saw a different number of explosions would end up with different runs.

One attempt or unlimited?

The games handle retries differently on purpose.

Why bother?

Arcade scores are only interesting when you can compare them. In an endless random run, a high score is partly skill and partly luck: maybe the threats spawned kindly. A daily run removes the luck from the comparison. If a friend scored higher than you on today's daily, they played the same game you did, and played it better.

It also gives each game a reason to come back to. There's always a new run tomorrow. Every game's daily is a click away from its guide page.

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