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Rounding is a promise when you show a player their odds

Development covered 23 Sep 2026 to 24 Sep 2026 (commit dates).

A player in Myriad Immortal Sect read "Tribulation success chance: 100.0%", pressed the button, and failed. The underlying chance was 99.96 percent. Nothing was wrong with the roll. The number on the screen had been rounded to the nearest tenth, and 99.96 rounds to 100.0.

Myriad Immortal Sect, the game this devlog is about. Play it free in the browser

To a programmer that is a formatting detail. To the player it is the game lying and then punishing them for believing it. This window turned into a small campaign about how odds are displayed, and the rules that came out of it are short enough to steal.

Round towards the outcome you cannot promise

The first rule is about direction. Rounding to nearest is the default everywhere, and for odds it is wrong at both ends.

Near the top, anything below certainty must never display as certainty. The odds card, the result card and the chronicle line now all round down, so 99.96 reads 99.9 and only a true certainty shows 100.0. Near the bottom, the mirror case: a chance that is possible but tiny used to print "0.0%", which says impossible. It now reads "<0.1%". The dispatch board's chip, which shows whole percentages, keeps anything uncertain inside 1 to 99, so a 99.7 percent errand shows 99 and a 0.3 percent one shows 1.

The principle is that the display should never claim more certainty than the roll has, in either direction. A player can live with "99.9% and I failed". They will not forgive "100% and I failed".

A Mystery Box offering three sealed boxes, with the best possible rarity shown underneath

One number, one formatter, everywhere

The second rule is about agreement. The same probability appeared on three surfaces: the odds panel, the result card, and the guidance card on the main screen. The guidance card rounded to a whole number, so it said "The Tribulation is open at 100%" directly beside a panel showing 99.6.

Two screens showing different numbers for the same fact are worse than either number alone, because the player now has to decide which one the game believes. Every place that shows a tribulation chance now goes through one display function. The chronicle also writes odds in the player's own number format, since a decimal comma and a decimal point are not interchangeable to someone reading in their language.

If you are preparing for a crossing yourself, the codex entry for the Transcendence Pill covers one of the items made for that moment.

Bonuses cannot pass the ceiling

The third rule came from the list of ways to improve your odds. A talisman adds fifteen points. At 88 percent it was still advertised as plus fifteen, which would make 103. Now each lever is capped at the headroom left under 100, so at 88 the talisman says plus twelve. That is a tiny change and it removes a whole class of "the numbers do not add up" confusion.

The dispatch board got the same scrutiny from the other side, since its chip was only recently relabelled after it turned out to be a power ratio rather than a probability. The guide to dispatching disciples on errands explains what that board is for.

The sect screen with rank, contribution and the Mission Hall board

The third question a return screen should answer

A different kind of number from the same window. When you come back after time away, the summary used to answer two questions: what happened while you were gone, and what changed. It never answered the one players act on, which is what they can now afford.

Time away pays levels, levels pay insight, and insight buys skill tree nodes. So after a gap that paid levels, the return toast and the panel now say how many nodes are within reach, using the same check the tree itself uses to decide whether a node can be bought. "You can now learn four nodes" is a reason to open the game's most important screen. A list of totals is not.

The skill tree and its four paths: cultivation, alchemy, sword and body

A smaller promise in the text

One more broken promise, of a different sort. Onboarding lets you pick a name and a face, several of the faces are women, and it never asks your gender. Eighteen quest strings still called the player a woodcutter's son, a village boy, him. They now say child, youth, novice, them. The Chinese text keeps its own narrator idiom, which reads differently there. The keystone nodes guide is a good next read if those newly affordable nodes made you curious.

The short version

Round odds towards uncertainty at both ends. Format them in exactly one place. Cap every bonus at the ceiling it can actually reach. And when a screen reports what happened, end with what the player can do about it now.

Check the odds yourself before your first storm: it is free to play in the browser.

Myriad Immortal Sect, the game this devlog is about. Play it free in the browser

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