Advent of Cascade 2026: one chain puzzle a day, 1 to 24 December
An advent calendar made of block puzzles. From 1 to 24 December 2026 a new door opens every day at midnight UTC, and behind each one is a single board to clear in an exact number of moves, built around a chain. Free in your browser, no sign-up.
The calendar gets harder as it goes. The first two weeks are short boards of two or three moves with 2- and 3-chains. From door 17 the boards need four moves and a 3- or 4-chain, the last four need five moves, and door 24 hides a 5-chain.
Doors stay open once they open, so a missed day is never lost. Your solved doors are kept in this browser, and each solve gives you a card to share with the day's number and your chain.
How to play
- Swap two blocks that sit side by side. A block can move into an empty cell.
- Three or more of one colour in a row or a column clear, and the blocks above fall.
- A fall that lands in a new match is a chain. Every door is built around one.
- Clear the whole board within the move limit. If you get stuck, reset and look for the fall.
The 24 doors
- Day 1: opens on December 1, 2026
- Day 2: opens on December 2, 2026
- Day 3: opens on December 3, 2026
- Day 4: opens on December 4, 2026
- Day 5: opens on December 5, 2026
- Day 6: opens on December 6, 2026
- Day 7: opens on December 7, 2026
- Day 8: opens on December 8, 2026
- Day 9: opens on December 9, 2026
- Day 10: opens on December 10, 2026
- Day 11: opens on December 11, 2026
- Day 12: opens on December 12, 2026
- Day 13: opens on December 13, 2026
- Day 14: opens on December 14, 2026
- Day 15: opens on December 15, 2026
- Day 16: opens on December 16, 2026
- Day 17: opens on December 17, 2026
- Day 18: opens on December 18, 2026
- Day 19: opens on December 19, 2026
- Day 20: opens on December 20, 2026
- Day 21: opens on December 21, 2026
- Day 22: opens on December 22, 2026
- Day 23: opens on December 23, 2026
- Day 24: opens on December 24, 2026
More in Cascade Puzzle
Frequently asked questions
When does each door open?
Door 1 opens at midnight UTC on 1 December 2026, door 2 on 2 December, and so on to door 24 on 24 December. Open doors stay open.
Do I need an account?
No. Play in your browser on a phone or a computer. Your solved doors are saved in this browser.
What if I miss a day?
Play it later. Every open door stays playable for the rest of the calendar and after it.
Cascade is an independent game, not affiliated with Nintendo or The Tetris Company.