z0mbies

The daily deduction puzzle

z0mbies is a free daily logic puzzle. Overnight, a virus swept through a building of 49 units. The morning survey maps who turned and who survived. You get one bank of autopsy probes: each probe reads the night a unit turned. Triangulate backward through the spread and find patient zero, the unit that turned first on night 0.

How to play

Probe a unit to read the night it turned. Every reading narrows where the outbreak began; the nights ripple outward from the source, so think like a contact tracer running time in reverse. The probe that reads night 0 closes the case. Run out of probes first and the case goes cold. Everyone gets the same case, and a new one opens every day at midnight Eastern.

Streaks and the leaderboard

Close cases on consecutive days to build a streak and climb the daily leaderboard. Beat par by closing in fewer probes and your share card shows it, spoiler-free.

Common questions

Is z0mbies free?

Yes. The daily case, streaks, and leaderboard are all free to play.

Do I need an account?

No. You can play right away. Signing in keeps your streak and record across devices.

When does a new case open?

Every day at midnight Eastern time.

What is patient zero?

The unit that turned first, on night 0, before the spread began. Your job is identification: find it, hand over the clean read, and the researchers take it from there.

What happens if I run out of probes?

The case goes cold and the reveal shows how it got past you. Your streak resets, and a fresh case opens the next day.

z0mbies is a 21x20 Media game. The rest of our daily games are at 21x20.com.