COMBILINGS

Combilings Devlog

Combilings was built quickly and tested in public. This page records the problems that were found after launch and the reasoning behind each fix. Most of them were not obvious from the code — they came from playing, or from someone reporting something strange.

Survival Mode was mathematically infinite

Two rules combined badly. The combo multiplier grew by 0.5 per clear with no ceiling, and every combo added two seconds to a clock that a move only cost about one second to advance. The player gained more time than they spent.

A simulation of two hundred runs confirmed it: the average score was 972 million and every run hit the one-hour limit of the simulation without the player ever losing. A score that large is not impressive, it is meaningless.

Three brakes fixed it. The multiplier caps at ×8. The time bonus dropped to 1.5 seconds and the clock caps at thirty, so time can be topped up but never banked. And the clock now accelerates by 40% per minute of play, which is what makes the mode a survival mode rather than an endurance test with no end.

A player found the exploit before we did

A tester reported that from a certain point he was earning enormous scores just by linking pairs. He was right, and the cap on the multiplier had not fixed it.

The reason was subtle. A pair raised the combo exactly as much as a path of six, but took half the time to make. The multiplier was rewarding tapping speed, not skill. Simulated side by side, spamming pairs scored 416,000 against 314,000 for someone playing well. The exploit was literally the best way to play.

The fix separates keeping a combo from growing one: a pair now refreshes the combo window but does not increase the multiplier, and it does not add time in Survival. On top of that, a length bonus of 15% per combiling above two makes long paths worth more than the sum of their parts. After the change, pair spamming scores 6,000 and dies in 28 seconds.

The install button paid for an install that never happened

An iPhone user reported that he pressed "Install App", received the coins, and nothing was installed. He was right.

Safari on iOS has no beforeinstallprompt event — installing is always manual, through the Share menu. The code, finding no prompt, showed a generic message and granted the reward anyway. The game was paying for something that had not occurred.

The rule changed: the reward is now granted when the installation is detected, never when the button is pressed. On Android it waits for the appinstalled event, because accepting a prompt does not guarantee the install completed. On iOS the button opens step-by-step instructions, and the coins arrive the first time the game is opened from the home screen.

Color Bombs were getting stranded

The original rule was that a Color Bomb only detonated when linked to a combiling of its own colour. It read well on paper and was miserable in practice: when that colour was not nearby, the bomb sat on the board as an obstacle. A reward had become a nuisance.

Measurement made it obvious — bombs were present on the board on 62% of moves, because they were accumulating rather than being used.

Now the bomb connects to any colour but keeps its own colour for the effect. It can never be stranded, and the interesting decision survives: hold it until the board is full of its colour. Bomb presence dropped to 28% per move, which is what being used instead of stuck looks like.

Smaller things, same pattern

• The level-complete screen promised 10 coins and the code granted 5 — a value left behind when the economy was centralised.
• Survival announced "+2s" per combo after the bonus had been reduced to 1.5.
• Leaving a game through the home button recorded no score at all, so anything achieved before quitting was silently lost.
• A global CSS rule forced every element to bold, which flattened the mode buttons into unreadable blocks of text.
• Players started with 250 coins, which bought a free retry before they had done anything. They now start at zero.

What this list is really about

Every item here was found by a person playing, or by measuring something instead of assuming it. None of them produced an error message. The lesson we keep relearning is that a game can be entirely free of crashes and still be broken in ways only a player will notice.