Library of Ruina: Complete Guide

A guide to Project Moon's card-and-dice "library battle simulation": how clashes, speed dice, stagger and emotion really work, how to build decks, how the floors and ranks progress, and how to push through the late-game difficulty spikes.

Researched September 2026 — current as of version 1.1.0.6a12 (November 2021, the final patch). The game is complete and no longer updated; the Steam Workshop is still active.

Quick Start

1. Clashing is everything. When your die meets an enemy die, both roll and the higher one wins. Win the clash and you deal damage; lose it and you take damage. Most fights are won by planning clashes, not by raw damage.
2. Speed decides who chooses. If your speed die is faster than an enemy's, you can target that enemy die directly and force a clash. Slower dice cannot redirect anything.
3. Stagger is a second health bar. Reduce a guest's Stagger Resist to zero and they cannot act next Scene and take far more damage. Staggering bosses is often easier than killing them.
4. Watch Light. Every page costs Light. Burning all of it on turn one leaves you with nothing when the boss's big pages show up.
5. Decks are 9 Combat Pages. Build around two or three things you want to do, with cheap pages to fill the gaps.
6. Burn books. Defeated guests become books; burning them gives Key Pages and Combat Pages. This is your entire gear progression.
7. Retry freely. Losing a reception is normal; you keep learning what the guests do. Their pages are visible, so each attempt teaches you the fight.
8. Do the Abnormality battles and Realizations as they unlock. They power up your floors.

The Basics

The Library, floors and librarians

You run a Library with ten floors, each themed on a Dewey-style category and each led by a patron librarian. They unlock in story order:

Each floor fields a team of librarians. You equip each librarian with a Key Page (their body: HP, Stagger Resist, speed dice, resistances and passives) and a deck of Combat Pages.

Receptions, Acts and Scenes

• You invite guests by spending books (a General Invitation) or through story invitations.
• Guests arrive for a reception, which is split into Acts (waves). Each Act plays out over Scenes (turns).
• Winning a reception turns the guests into books.
• Guests come in difficulty tiers that match the story: Canard, Urban Myth, Urban Legend, Urban Plague, Urban Nightmare, Star of the City and Impuritas Civitatis.

Combat in Depth

Dice types

Resistances

Key Pages list resistances to Slash, Pierce and Blunt for both HP and Stagger, on a ladder from Fatal and Weak through Normal to Endure and Ineffective. Hit enemies with the damage type they are weak to, and pick Key Pages whose weaknesses do not line up with the guests' main damage type.

Speed dice and targeting

• Each character rolls one or more speed dice per Scene. Each die holds one Combat Page.
• A faster die can target an enemy die to force a clash.
• If you do not redirect an enemy attack, it becomes a one-sided attack: the target just takes it (unless they have Counter dice).
• The "Whoopsie-daisy!" achievement is for entering a Scene with no dice slotted. Don't do that in a real fight.

Light and card draw

• Pages cost Light. Characters recover Light and draw pages between Scenes, and some pages and passives restore extra Light or draw extra pages.
• A curve matters: mix 0-1 cost pages with a few expensive payoff pages so you have something to play every Scene.

Stagger

Stagger Resist drops as you take stagger damage. At zero the character is Staggered: they skip the next Scene and take heavily increased damage. Use Stagger both ways:

• On guests: focus Blunt or high-stagger pages on a boss, then unload damage while it is staggered.
• On your librarians: use Evade to recover Stagger and avoid giving the boss a free turn.

Status effects

The common ones: Burn, Bleed, Paralysis, Fragile, Feeble, Disarm, Bind, and buffs like Strength, Endurance, Protection and Haste. Bleed and Burn chip damage over time; Paralysis weakens dice; Fragile and Feeble increase damage taken and reduce damage dealt; Bind slows. Strength and Endurance add to your offensive and defensive dice.

Emotion, Abnormality pages and E.G.O

• Clashes, dice results and damage generate emotion. As a team's average emotion rises, the Emotion Level goes up, to a maximum of 5.
• On each level up you choose an Abnormality page from the floor. Green (Awakening) pages are pure benefits; red (Breakdown) pages are stronger but carry drawbacks. You can hold up to five per battle.
• At higher emotion, the floor's E.G.O pages become available: powerful Combat Pages shared across the team.
• Guests' emotion also rises. That makes them more dangerous, and it is also how you earn rarer book rewards.

Mass attacks

Some guests (and some of your pages) use Mass Attacks, which hit every opponent. They cannot be clashed normally. Prepare with high Block or Evade dice, accept the hit, or kill or stagger the user before it fires. Some pages, such as Ever-repeating Performance, interact specially with Mass Attacks.

Progression

Books, Key Pages and Combat Pages

• Burn books to receive the pages listed in that book. Some books have rare drops, like Objet d'art pages.
• Key Pages differ enormously. A late Key Page with more speed dice changes a librarian's role.
• Passive attribution lets you transfer passives from one Key Page to another within a passive cost budget. This is where builds get strong.
• Battle Symbols are small stat and effect boosts earned by meeting conditions in battles.

Floor Realizations

Each floor eventually offers a Realization: a multi-phase battle with puzzle-like rules, centred on that floor's patron librarian. Clearing it unlocks the floor's special E.G.O pages. Completing all Realizations leads to the true ending.

Story arc

You play Angela, an AI seeking "the one perfect book" to become human, with Roland, a Fixer who ends up working at the Library. The City's Fixers, Associations and Wings supply your guests. Major story fights include the Reverberation Ensemble and famous figures like the Purple Tear. Much of the late story ties back to Lobotomy Corporation, which is worth knowing but not required.

Deckbuilding Principles

1. Pick a win condition per librarian. Examples: stacking Bleed, dishing out Burn, heavy Blunt stagger, or evade-counter play.
2. Nine pages, few costs. Several 0-1 cost pages keep you playing every Scene; one or two high-cost payoffs win fights.
3. Duplicate your best pages. Consistency beats variety.
4. Match dice to the job. A page with an Evade die is great in slow, defensive slots; multi-hit offensive pages belong on fast dice where you choose the clash.
5. Build the floor as a team. One librarian applying Paralysis or Fragile makes everyone else's damage better.
6. Revisit decks every chapter. New Key Pages with more speed dice make old decks obsolete.

Community deck guides are organised by rank on Steam, from Urban Plague to Impuritas Civitatis, and are a good reference once you hit a wall.

Common Mistakes to Avoid

• Letting enemy big pages go one-sided. If the boss's big page is on a die you can reach, clash it with something that can win or defend.
• Ignoring resistances on your Key Pages and theirs.
• Spending all Light early and having nothing for a key Scene.
• Taking red Breakdown Abnormality pages blindly. Read the drawback first.
• Hoarding books. Burn them; pages are the point.
• Not using passive attribution. Unequipped passives on spare Key Pages are wasted power.
• Forcing a reception that is well above your rank. Go back and farm the previous rank's books for better pages.

Advanced Tips

• Speed manipulation (Haste, speed-boosting passives) gives you control of every clash. Prioritise it once available.
• Sacrificial targeting: sometimes the best play is letting a sturdy librarian eat a one-sided hit while your faster dice win the clashes that matter.
• Stagger bosses before their big turn. A staggered boss skips its devastating Scene.
• Use Counter dice for one-sided attacks you can't clash.
• Keep one flexible librarian on each floor whose deck handles Mass Attacks defensively.
• Workshop: the game has official custom reception and mod tools, including DLL support and story editing. Workshop receptions extend the endgame, but disable mods if something breaks. The game can safely remove content from unsubscribed mods.

FAQ

Do I need to play Lobotomy Corporation first? No, but the story hits much harder if you know it. Library of Ruina is a direct sequel, and Limbus Company continues the setting.

How many Combat Pages are in a deck? Nine.

Is Library of Ruina still getting updates? No. The last patch, 1.1.0.6a12, came out on 18 November 2021. The game launched on PC and Xbox One on 10 August 2021, and Switch and PS4 versions followed on 25 April 2024. The Steam Workshop (with the official custom reception tool) is PC-only.

What counts as the true ending? Completing every floor's Realization unlocks it.

Why do I keep losing to one boss? Usually it's one of three things: its big page goes one-sided every turn, your damage type is wrong for its resistances, or you are not staggering it. Check its pages and resistances and plan clashes around them.

Is there an artbook? Yes, as paid DLC in PDF form, available in several languages including simplified Chinese.

Sources

• Steam store page
• Steam achievements list
• Patch notes 1.1.0.6a12
• Patch notes 1.1.0.6 (custom reception tool)
• Wikipedia: Library of Ruina
• Steam Community guides hub