Free
With Ads
About
Collatz Hailstone Link — a relaxing number-merge puzzle built on one of math's most famous mysteries: the Collatz
conjecture (the "3n+1" problem).
Drag and merge numbered tiles, watch each sum bounce through the hailstone sequence, and chase the highest — or
lowest — final number you can reach. Easy to learn in seconds, deep enough to keep you coming back for a better
score.
HOW TO PLAY
• Drag one tile onto another (or tap one, then another) to merge them.
• The two values are added, then the Collatz rule is applied to the sum:
- Even sum → divide by 2 (the tile turns blue)
- Odd sum → multiply by 3 and add 1 (the tile turns orange)
• Chain the same color in a row to build a streak bonus.
• Keep merging until a single tile remains. Push that last value as high — or as low — as you can!
FEATURES
• Pure one-finger gameplay — merge with a drag or a tap.
• 7 board shapes: Square, Hexagon, Triangle, and four hybrid layouts.
• Three-part scoring: turn points, streak bonuses, and a final bonus based on your last number.
• Undo your recent moves to plan the perfect chain.
• Records screen — sort your runs by score, max value, final value, and date.
• Global online leaderboards — compete on both High Score and Final Max.
• Light & Dark themes.
• English & Korean language support.
• Play offline, anywhere — no account required.
WHY YOU'LL LOVE IT
A quick puzzle for a coffee break, a brain teaser for math lovers, and a satisfying score-chaser for everyone in
between. Every board is a fresh little puzzle in number theory — no two runs feel the same.
Merge the numbers. Ride the hailstones. Beat your best.
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What's New in Collatz Hailstone Link
0.6.0
July 5, 2026
* 2026/07/05 Version 0.6.0 - Bug fix








