Erumaru
JA 日本語

About the game

Erumaru is a single-player PvE auto chess roguelite for PC, set in a post-apocalyptic world forty years after its man-made sun went out. Pure 2D, built in Godot 4.6 with C#. Everything below comes from the design documents of the game

The game in one paragraph

Forty years ago the man-made sun Eru went dark over the world of Erumaru, and the Haze crept over the land: dead light that drains colour and will from everything alive. You are the Lanternkeeper. You carry the Lantern where the afterglows of fallen heroes live, and you lead a squad through three acts of ruins to the Lamp Room at the top of the Spire, where the Empty Mirror waits. Between fights you buy and merge heroes, assemble items from components, move perks around, choose relics and your path on the map. The fight itself runs automatically: up to 10 heroes against up to 10 mobs on an 11 by 11 board. Heroes grow to level 100 like in Dota, abilities gain ranks, and every hero has its own mechanic and a look you recognise at a glance. A lost run does not reset everything: the Lantern gains levels and remembers new heroes, items, perks, relics, lands and modes

Six pillars

Every hero is special

Each of the 100 heroes has a mechanic you cannot confuse with its neighbour: a trait, one or two abilities and an Awakening at level 100. The people sets the theme, the calling sets the role. And visually every hero is a MOBA-style silhouette: one bright shape, one main detail, one colour, readable from a camera high above the board

Nothing goes to waste

Components become items, items are woken by sparks of Eru, identical perks merge into a higher rank, spare hero copies become experience. In a world where everything is broken, every bolt gets fixed and put to use

Decisions over reflexes

Placement, synergies, the order of upgrades, the route on the map and the economy. A fight can be watched at normal speed or skipped, the result does not change

A fair fight

The simulation is deterministic: a fight with the same seed always plays out the same way. Everything a tooltip says works exactly as written

A long road

Meta progression for 50 or more hours: 50 Lantern levels, 20 steps of Thickening, the Descent into the Inferno, an archive with the lore

Colour against grey

Ruins, sky and mobs under the Haze are washed out; heroes and peoples hold on to their colour. Every victory gives the land a little colour back, and you see it on the board

The run

  • Three acts of 13 floors each: an Outpost without a fight and 12 map nodes, the last of them the boss. Then a three-floor finale in the Lamp Room of the Spire. 42 floors, 60 to 90 minutes
  • At the start of each act you pick one of three lands of that act. The fights of the land happen on its board
  • The map of an act is 12 columns of 3 to 4 branches, connected like in Slay the Spire. The first column is always a fight, the seventh is the guardian of the land, the eleventh is a rest, the twelfth is the boss
  • Nodes: fight, elite, guardian, boss, bazaar, workbench, chapel, cache, rest, signal and 40 text events with choices
  • Economy on salt: 8 at the start, 6 to 15 per fight, interest of 1 per 10 saved up to 5. The shop shows 5 heroes, a refresh costs 2, freezing is free
  • Reach decides how many heroes fit on the board, from 3 to 10, and which ranks the shop can roll
  • Heat is the fire of the Lantern: it starts at 5, a lost fight costs 1, a lost elite, guardian or boss fight costs 2, a rest gives 1 back. At zero the run ends
  • The finale: the Keymasters on floor 40, the Voice of the Mirror on 41, the Empty Mirror on 42 with three phases, a fourth on Thickening 20. The Mirror copies the strongest ability of your squad
  • After a win, the Descent: floors 43 and up, mobs gain levels every floor, a Mutation every five floors, a record table

Heroes

  • 100 heroes: every pair of 10 peoples and 10 callings exactly once. Ranks I to V, the price in salt equals the rank
  • Three attributes as in Dota: Strength, Agility and Intelligence. Health, attack, attack speed, armour and spell power derive from them
  • Levels 1 to 100 during a run. Ability 1 gains ranks at levels 20, 40, 60 and 80, ability 2 opens at 30, the Awakening at 100 adds an effect to the hero's trait
  • Stars: three copies make two stars, three two-star copies make three stars. A copy of a three-star hero becomes three levels
  • Six item slots and four perk slots per hero. Items and perks can be moved between fights
  • Ten callings: Warlock, Warrior, Assassin, Mage, Engineer, Shaman, Healer, Summoner, Ranger, Guardian

Items, perks and relics

  • 100 items: 10 components, any two different components combine into one of 45 items and two identical ones into one of 10 reinforced items. A spark of Eru wakes 25 of them into legendaries. 10 artifacts drop from bosses, each with a price
  • 100 perks with three ranks: 40 common, 30 rare, 20 epic, 10 legendary. Two copies merge into the next rank
  • 100 relics for the whole squad: 30 common, 25 rare, 15 epic, 10 legendary, 10 cursed and 10 boss relics. They change the economy, synergies, stats, combat rules and the map
  • Scorn Burning Horn Scorn Burning Horn
  • Alva Northern Lights Alva Northern Lights
  • Amani, Mistress of Zenith Amani, Mistress of Zenith
  • Niara, Night Sight Niara, Night Sight
  • Halm Vault Door Halm Vault Door
  • Kasyan, the Dead Engineer Kasyan, the Dead Engineer
  • Rina Dogfish Rina Dogfish
  • Shi-Lo the Iridescent Shi-Lo the Iridescent
  • Krivda the Crow Krivda the Crow
  • Master Yan Formwork Master Yan Formwork
  • Bella Fire Horn Bella Fire Horn
  • Nora Nailgun Nora Nailgun
  • Frost wolf Frost wolf
  • Mast harpy Mast harpy

The world

Two hundred and fifty years ago the ten peoples of Erumaru welded their lamps into one man-made sun, Eru, and raised it over the Spire on the Hub plateau. Its light ran along light lines into every land, held the union of peoples, the Lightgrid, and locked the well of raw light under the Hub, the Inferno

The Keeper of Eru, now called the Empty Mirror, tried to take all the light for himself. Eru cracked and went dark, ten large shards fell one into each land, thousands of sparks scattered across the world, and from the cracked core came the Haze. Machines stopped, cities emptied. The legendary heroes of all peoples climbed the Spire and died there, but their light remained in the last relic of the Lightgrid, the hand Lantern

Mana is the light of Eru settled in living bodies: it is knocked out by blows, gathers in battle and bursts out as abilities. Statuses are what light does to a body. The mobs of a land are its people and beasts touched by the Haze, and the bosses are the former guardians of their peoples who still hold the shards of Eru

Ten lands

Every land has its own people, its own ground under the board, a guardian in the middle of the act and a boss at the end. Three lands per act, one of them open from the start, the rest remembered by the Lantern

  • Act I · Dam FolkThe Great Damboss Tarvin, the Torn Sluice
  • Act I · ClimbersKrongradboss Forefather Rootbreaker
  • Act I · TidefolkThe Sunken Portboss Captain Dead Calm
  • Act II · DepartedThe Blind Tunnelsboss the Matron of the Terminus
  • Act II · MoultersThe Settling Pondsboss the Mother of the Drains
  • Act II · NoonbornThe Glass Desertboss the Sphinx Without an Answer
  • Act III · IcebreakersThe Ice Bowlboss the Snow Mother
  • Act III · WeldersThe Furnaceboss Cast-Iron Head
  • Act III · HighriggersThe Mast Ridgeboss Great-Grandfather Thunder
  • Finale · Hellborn nearbyThe Lamp Room of the Spireboss the Empty Mirror

Twenty synergies

Unique heroes of one people or one calling on the board count towards thresholds of 2, 4 and 6. The Hellborn count differently: exactly 1, 3 or more, 5 or more

  • Living Dam · Dam Folk
    damage reduction for every neighbouring ally, at 6 the whole squad gets it
  • Through the Branches · Climbers
    evasion, at 6 the next attack after a dodge hits harder
  • Damp Earth · Departed
    enemy armour melts, at 6 the first fallen Departed rises again
  • Zenith · Noonborn
    abilities set targets burning and blind them, at 6 a burst of spell power at the 15th second
  • Freeze-Up · Icebreakers
    attacks stack Chill into Freeze, frozen enemies take more damage and shatter
  • Welded Seam · Welders
    item stats grow, at 6 a shield once per fight when low
  • Stone Dive · Highriggers
    flight, heavy first strikes, at 6 the squad starts the fight in the air and dives
  • Old Skin · Moulters
    attacks stack poison, poison heals, at 6 a lethal hit is shed with the skin once per fight
  • High Water · Tidefolk
    the fight runs in tides: mana on the flood, damage on the ebb, shields for everyone at 6
  • Indenture · Hellborn
    a lone Hellborn hits hard with lifesteal, three or more collect souls from the dead
  • Dark Pact · Warlocks
    spell lifesteal for warlocks, then the squad, then faster damage over time
  • Battle Fervor · Warriors
    more damage, less damage taken, attacks cleave
  • Shadow · Assassins
    assassins leap to the farthest enemy, crit chance and crit damage, invisibility on kills
  • Resonance · Mages
    enemy magic resistance drops, mages gain spell power, at 6 the first ability casts twice
  • Workshop · Engineers
    stronger constructs, helper turrets, destroyed constructs explode
  • Spirit Voices · Shamans
    the strongest enemies are hexed at the start of the fight, at 6 shaman abilities silence
  • Light of Hope · Healers
    stronger healing and shields, cleansing, at 6 the first fallen ally rises
  • The Call · Summoners
    stronger summons, a Spirit for every summoner, at 6 a fallen summon returns as a copy
  • Volley · Rangers
    attack speed and range, at 6 every fourth shot pierces the line
  • Bastion · Guardians
    guardians take less damage, share it with neighbours, at 6 they absorb part of the damage dealt to allies next to them

Between runs

  • The Lantern has 50 levels and gains experience for floors, bosses and victories. Every level gives a point for the Homestead, a tree of small starting bonuses
  • Unlocks by schedule: 30 heroes of rank I from the start, higher ranks with levels, legendary heroes through Kindlings, trials where you repeat a hero's feat. Items, perks, relics and lands open the same way
  • 12 Filters change the starting rules of a run: more Heat, free shop refreshes, two components at the start, a legendary relic and more
  • Thickening: 20 steps of difficulty that stack, from tougher mobs to a fourth phase of the Empty Mirror
  • The Descent after a win, a daily run with a shared seed from Lantern level 5 and Sorties with quirks from level 20
  • An archive with the lore of every hero, mob, item and land, and achievements

Where the game is now

Erumaru is built in Godot 4.6 with C#. The battle simulation is a separate library without graphics that produces an event log the game replays. The run with its map, economy and saves, the meta progression and the full catalogue of 100 heroes, 100 mobs of ten lands with bosses, 100 items, perks and relics and 40 events are in the game and are being balanced with thousands of simulated fights. Heroes and mobs are animated from parts on skeletons in the ceramic style. The art of the ten peoples and ten lands is being drawn