Steam app 3733510 · updated 12 Sep 2026, 19:56 UTC
Lead adorable warriors to form an adventure team to work and adventure on the computer desktop. Defeat the warriors to save the world. Rich nurturing and collection elements, idle and slack off to earn money and fight monsters!
717 hourly samples, with the daily peak drawn over them. Weekends are shaded.
8 months, February 2026 to September 2026. The highest number of people in the game at once, each month, on a time axis -- a gap in the record stays a gap.
The highest number of people in the game at once, each month. Four, because four is as far back as the source keeps anything finer than one figure a month.
31 days, each one the highest figure that day. The source keeps no hourly detail this far back. Weekends are shaded.
31 days as the curve, each the highest figure that day. Behind it, 436 hourly samples from 13 Aug, which is as far back as the source keeps every hour. Weekends are shaded.
12 days as the curve, each the highest figure that day. Behind it, 281 hourly samples. Each dip is a night. Weekends are shaded.
Book of Fei was released on 20 Feb, 2026.
| Language | Full audio |
|---|---|
| English | |
| Simplified Chinese | |
| Traditional Chinese | |
| Japanese | |
| Korean |
A blank audio cell means full audio was not marked in the returned language list.
27 achievements in total.
50 developer announcements, Apr 2026 to Jul 2026 · times in UTC
Hi, Brave Hero! Arya here. I heard the call from our Mac heroes — so I brought the fix squad to give your Mac a well-earned breather!Attempted Fix: Mac Memory Overflow: Attempted to fix a memory overflow issue that could occur after…
YuntheliaHi, Brave Hero! Arya here. This update brings a whole new set of tools for your Mythic Gear~New Feature: Mythic Gear Attribute Reroll: Reroll the value of a chosen random attribute on your Mythic Gear, bringing every piece closer to your…
YuntheliaHi, Brave Hero! Arya here. Two small battle fixes this time to make your fights feel smoother~Fix: Battle Gold Pop-Ups: Fixed an issue where battle gold pop-ups behaved abnormally in certain situations.Fix: Ultra-Wide Screen Battlefield…
Patch notesHi, Brave Hero! Arya here. Just a small fix this time so your achievements sync without a hitch~Fix: Steam Achievement Sync: Fixed an issue where Steam achievements failed to sync in certain situations—now your hard-earned achievements…
Patch notesHi, Brave Hero! Arya here. I went around and smoothed out a few of the bumpy little spots in your adventure this time~Fix: Temple Crash: Fixed an issue where the Temple could freeze or crash in certain situations—explore with peace of…
Patch notesHi, Brave Hero! Arya here. The winds over the Dragon Continent have been restless lately—maybe the dragons are watching your journey!Improvement: Dragon's Blessing: Elemental Dragon ability drops now feel smoother, and a new mercy…
Patch notesHi, Brave Hero! Arya here. The winds over the Dragon Continent have been restless lately—maybe the dragons are watching your journey!Improvement: Dragon's Blessing: Elemental Dragon ability drops now feel smoother, and a new mercy…
Patch notesHi, Brave Hero! Arya here. We fixed a little 777 hiccup and made your work plots harvest even smoother!Fix: 777 Jackpot Compensation: Fixed a bug where the 777 jackpot could not be obtained in some cases. If you were affected, just reopen…
Patch notesHi, Brave Hero! Arya here. This update makes temple challenges smoother and keeps your game screen right where it should be!Improvement: Temple Auto-Challenge Option Experience: Further polished the "Auto-Challenge Next Difficulty" option…
Patch notesHi, Brave Hero! Arya here. This update gives you more control over your adventure — toggle guidance your way and let the forge temple auto-challenge do the work for you!New Feature: Game Guidance Master Toggle: A new master toggle has been…
Patch notesHi, Brave Hero! Arya here. Artifacts can now evolve through infusion — time to power up!New Feature: Artifact Advanced Infusion: When conditions are met, artifacts can be further evolved through infusion, greatly enhancing their bonus…
Patch notesHi, Brave Hero! Arya here. Challenge chapters just got tastier — there are new rewards waiting for you!New Feature: Challenge Chapter Completion Rewards: After completing all plots in a challenge chapter, you can claim Soul Brew rewards…
Patch notesHi, Brave Hero! Arya here. Ever felt like the battle screen was sitting a bit too high or low? Now you're in control — just uncheck the snap toggle in Settings and drag the screen height exactly where you want it!New Feature: Snap Toggle &…
Patch notesHi, Brave Hero! Arya here. I've got a super handy little feature for you this time — your Peak Talents now support three loadout presets you can swap between instantly!New Feature: Peak Talent Loadouts: Save up to three Peak Talent…
Patch notesHi, Brave Hero! Arya here. We tidied up the battle info display this time — cleaner screen, clearer numbers!Improvement: Floating Battle Info Display: When you turn off "Show Floating Battle Info" in settings, skill shouts and special…
Patch notesHi, Brave Hero! Arya here. Got some fixes and quality-of-life improvements to make your adventure run smoother than ever!Fix: Elemental Dragon Wind Blade Damage: Fixed a bug where the Elemental Dragon's Wind Blade ability dealt far less…
Patch notesHi, Brave Hero! Arya here. Found a sneaky little gremlin hiding in your Mythic Gear — and I've shown it the door!Fix: Mythic Gear Affix Anomaly: Fixed a bug where Mythic Gear could generate incorrect random affixes in certain situations.…
Patch notesHi, Brave Hero! Arya here. Shopping at the store just got a whole lot smoother — let me show you what's new!Improvement: Purchase Experience: Massively increased the max purchase limit for equipment crates so you can stock up in one go!…
Patch notesHi, Brave Hero! Arya here. Tired of digging through your stash for that one Mythic piece with the right affixes? I've got something for you!New Feature: Mythic Gear Marking Assistant: Set your preferred affix types and the system will…
Patch notesHi, Brave Hero! Arya here. Brought you some display improvements so your adventure looks great no matter the screen!Fix: Widescreen & Ultra-widescreen UI: Fixed interface layout issues on widescreen and ultra-widescreen monitors. UI now…
Patch notesHi, Brave Hero! Arya here. This update is all about making your battles run smoother behind the scenes.Attempted Improvement: Endless Defense & Forge Temple Memory Leak Fix: Optimized memory usage in these two battle modes to reduce lag and…
Patch notesHi, Brave Hero! Arya here. Did a little spring cleaning in the adventure world today — chased out some memory-hogging gremlins and gave that stubborn Lucky Star achievement a gentle nudge!Attempted Improvement: Memory Overflow: Worked on…
Patch notesHi, Brave Hero! Arya here. Gave that one-click completion feature a stern talking-to — it was acting up a bit, but it's back in line now!Fix: Challenge One-Click Completion: Fixed a bug where the chapter one-click completion feature could…
Patch notesHi, Brave Hero! Arya here. Got a sweet quality-of-life feature for you today — no more clicking through every leftover plot in challenge chapters!New Feature: One-Click Challenge Plot Completion: After clearing a challenge chapter, you can…
Patch notesHi, Brave Hero! Arya here. Today's patch smooths out some rough edges and squashes pesky bugs.Fix: Talent Panel Stutter: Fixed the stuttering issue in the talent panel. Don't worry, the special "mechanic" is still there!Attempted Fix: Light…
Patch notesHi, Brave Hero! Arya here. This patch tackles a few visual and loot bugs that have been annoying everyone.Fix: Talent Tooltip Truncation: Fixed an issue where some tooltip text in the talent screen couldn't fully display. All descriptions…
Patch notesHi, Brave Hero! Arya here. Another round of polish — focused on memory, chain mythic forging, and elemental dragon FX alignment.Attempted Improvement: Runtime Memory Usage: Attempted to further reduce the game's runtime memory footprint…
Patch notesHi, Brave Hero! Arya here. The Book of Doors speaks two new languages this patch — welcome to even more brave heroes joining our world!New Feature: Japanese / Korean Support: The game now supports 日本語 and 한국어, switchable anytime from the…
Patch notesHi, Brave Hero! Arya here. This patch finally adds a one-click level-up for elemental dragons, polishes the reset flow further, and squashes two combat bugs that were getting on everyone's nerves.New Feature: One-Click Elemental Level-Up…
Patch notesHi, Brave Hero! Arya here. This patch focuses on growth-experience polish — resetting your dragon no longer feels like flushing it all away, and mythic forging is a lot less clicky.New Feature: Lock Abilities on Level Reset: Added the…
Patch notesHi, Brave Hero! Arya here. More polish for Dragon Continent — aiming to run smoother, look easier on the eyes, and stop those flashy effects from stealing the spotlight.Attempted Improvement: Dragon Continent Idle Combat Performance…
Patch notesHi, Brave Hero! Arya here. This patch polishes details — making Ball King fights fairer, the Adventurer's Handbook nicer to flip through, and giving Dragon Continent combat a tentative speed boost.Improvement: Ball King HP-Drain Mechanic…
Patch notesHi, Brave Hero! Arya here. This patch mainly puts the Book of Doors on a diet — long idle sessions should feel a lot lighter and steadier now.Improvement: Runtime Memory Usage: Significantly reduced the game's runtime memory footprint. Long…
Patch notesHi, Brave Hero! Arya here. Another round of fixes circling around the elemental dragons and cards — tightening up energy skills and quality-tier effects.Attempted Fix: Quality-Tier Ability Scaling: Attempted to fix the issue where some…
Patch notesHi, Brave Hero! Arya here. Another round of fixes and polish — patching up the worst snags that were getting in the way of your idle runs.Fix: Auto-Challenge Glitch: Fixed the issue where auto-challenge caused combat anomalies on Dragon…
Patch notesHi, Brave Hero! Arya here. Just a quick round of fixes and polish this time — sweeping up the last few loose ends.Fix: Elemental Dragon Appearance FX: Fixed the issue where elemental dragons' elemental appearance effects weren't displaying…
Patch notesHi, Brave Hero! Arya here. The big one is really here — a Void Rift tore open the core of the Light Continent, so I hatched you a young dragon from the Book of Scrolls. Take it from here and let's take the world back!New Mode: Dragon…
YuntheliaHi, Brave Hero! Arya here. I've tuned up the battlefield items and polished a few rough edges!Improvement: Battlefield Item Refresh Logic: Reworked the cooldown timing and calculation for battlefield interactive items — the refresh rhythm…
Patch notesHi, Brave Hero! Arya here. A quick patch to squash some pesky battle bugs!Bug Fix: Battlefield Item Cooldown: Fixed a bug where cooldown timers on battlefield interactive items were not working correctly. They should behave as expected…
Patch notesHi, Brave Hero! Arya here. This update brings a much-requested feature to Endless Defense mode!New Feature: Endless Defense Advanced Affix Reset: Endless Defense mode now supports advanced affix resets! If you're unhappy with your current…
Patch notesHi, Brave Hero! Arya here. Just a small patch this time to improve auto-challenge stability.Attempted Fix: Temple Auto-Challenge Stopping: Attempted to further fix an issue where the Forge Temple auto-challenge could stop running under…
Patch notesHi, Brave Hero! Arya here. This update makes crafting perfect Mythical Equipment easier than ever, and the Forge Temple just got a whole lot more convenient!New Feature: Advanced Mythic Crafting: A brand-new advanced crafting system is…
Patch notesHi, Brave Hero! Arya here with some quality-of-life improvements!Improvement: Mythical Equipment activation & equipping: Streamlined the activation and equipping flow for Mythical Equipment, making it smoother and more…
Patch notesHi, Brave Hero! Arya here with some polish and fixes!Improvement: Artifact UI layout: Optimized the Artifact panel layout and fixed elements that were overflowing outside their frames. Everything looks much tidier now!Attempted Fix…
Patch notesHi, Brave Hero! Arya here. The game log just got a nice upgrade!Improvement: Expanded game log: The log now tracks your activities in the Forge Temple, Infinite Challenge, and more. Every run and reward is recorded so you can review your…
Patch notesHi, Brave Hero! Arya here. This update gives your Artifacts a brand-new way to grow even stronger — Artifact Infusion!New Feature: Artifact Infusion: Challenge higher difficulty tiers in the Forge Temple to earn Artifact Shards. Use them to…
Patch notesHi, Brave Hero! Arya here. Quick patch to address a frustrating issue!Attempted Fix: Characters vanishing in Forge Temple: Fixed an issue where some characters would mysteriously disappear during Forge Temple battles. If it still happens…
Patch notesHi, Brave Hero! Arya here. Two quality-of-life improvements for the Forge Temple this patch!Improvement: Temple battle hero movement and enemy spawn logic: Optimized hero movement and monster spawn positioning in Forge Temple battles for a…
Patch notesHi, Brave Hero! Arya here. Small but handy patch for anyone managing their Mythical Equipment collection!Quick Disenchant expanded: The one-click disenchant feature now supports red and rainbow quality Mythical Equipment, making inventory…
Patch notesHi, Brave Hero! Arya here. This patch focuses on making Temple and Defense modes feel much smoother — especially that annoying issue where switching your lineup for Temple would mess up your regular formation. That's finally…
Patch notesWhat Steam runs, and with what. Straight from the app configuration.
| Description | Executable | Arguments | Platform | |
|---|---|---|---|---|
| Launch | BookOfFei.exe | windows | ||
| Launch | BookOfFei.app | macos |
The folders Steam Cloud syncs. The root is a token Steam uses for a location on your own machine, not a path this page can know.
| Root | Folder | Files |
|---|---|---|
WinAppDataLocalLow | TaoStudio/BookOfFei | *.es3 |
It runs on public data and somebody's spare time.
https://paypal.me/KintaroPalPay[email protected]0x4d559C765AA8BFe336E36d5b76024926767eD38dTJtctWU9uetJaTBoSybd1RErW7n9duTKVG