Echoes of Aether

01The hook

I started from something that bugs me in a lot of RPGs: the final boss is just a monster with a bigger health bar and a predictable script. Echoes of Aether makes a different bet. Its enemies don’t fake intelligence: they learn.

Behind it sits an invisible lab in NetLogo, where whole species fight thousands (sometimes millions) of battles in the dark. What survives isn’t a cutscene: it’s a JSON file of Q-values that the .NET runtime imports as combat instinct. Not “AI on a slide”, but a learning architecture stitched into the lore.

Aetherion doesn’t need another monster with a longer health bar. It needs adversaries who remember how you beat them yesterday.

— from the design notes

02Screenshots

Top-down pixel-art exploration with other players on the same map. Click an image to enlarge it; inside, the ← → keys switch screenshots and Esc closes.

03The world: Aetherion

For centuries the Veil, a barrier forged by ancient mages and warriors, kept the mortal world apart from the Void. Then it cracked. Forgotten creatures bleed out of the fissures, forests sicken, the dead wake with half their memories, and shadows learn to wear human names.

The order of the Sentinels of the Veil vanished after the first great rupture. The player carries a Mark tied to that order; it throbs near the fissures like an instrument tuned to the wrong kind of silence.

The tone is light dark fantasy: heroism, mystery, ancient magic, sacrifice, hope, and humour when it counts. No gore, no adult content: it’s rated All ages.

Pocket glossary

In the lore an Echo isn’t just a monster: it’s fighting memory. In the code, that’s the perfect metaphor for trained policies: patterns that survived thousands of simulated deaths and came back to the living world.

04Places

No “area 1, area 2” here. Every place has its own name and art direction, and the world map and diagnostic maps already exist as finished art.

Map legend

• Valebruma · a city under purple storms; starting point, forge, healing, gossip and fear
• Lago Espelhado · water that shows you what you’d rather not see
• Santuário Oculto · a trail and ritual silence
• Bosque Enfermo · corrupted green, beasts and spirits that beg for healing or fire
• Minas de Ferro Negro · tunnels, traps and Grothar, the Heart of the Mine
• Torre de Arken · puzzles, grimoires, automatons and Seraphine: fight her or redeem her
• Fortaleza da Fenda · the final siege against Malachar, Herald of the Rift
• Caverna dos Ecos · descents beneath Valebruma: magma floors, bridges and crystals

05Playing together: groups, quests and combat

The map is shared: player presence syncs in real time over SignalR, and the HUD shows your group and who’s online in the area. In the screenshots you can spot name tags over characters, the group panel and the leave button, plus touch controls.

Arc 1: the quest chain

1. PrologueA Noite das Cinzasa tutorial under attack; the Mark awakens
2. Ch. 1Estrada dos Sussurrosambushes, a moral choice and an abandoned Sentinel outpost
3. Ch. 2O Bosque Enfermohealing, a mini-boss and a runic fragment
4. Ch. 3As Minas de Ferro NegroGrothar
5. Ch. 4A Torre de ArkenSeraphine: blade or mercy
6. Ch. 5A Fortaleza da FendaMalachar and three endings

Stable narrative flags (SavedBlacksmith, SeraphineSpared, ArtifactPreserved…) make the epilogue remember what you did, not just the level you grinded to. There are three endings:

Origins, classes and factions

• Three origins: Guardian of Valebruma (duty and defence), Wandering Scholar (mana, grimoire and dangerous questions) and Borderlands Survivor (agility, pragmatism and a torn map). None is better on paper; each changes the world’s first smell.
• Warrior, fuelled by Fury: melee, stances and taunts. Paths: Guardian, Berserker and Weapon Master.
• Mage, with mana and Resonance, which rewards sequences (the Aether likes rhythm). Paths: Pyromancy, Cryomancy and Arcane.
• Factions: the Sentinels of the Veil (a historical ghost), the Valebruma Guard, the Cult of the Rift, the Wandering Market and the Arken Archive.

Turn-based combat that explains itself

Damage, loot, gold and XP are never born on the client: cheating dies at the door. The log and tooltips explain why you bled. Fire against skin that melts, ice against hot blood, resistances that punish lazy magic.

Difficulty runs from Story to Normal, Veteran and Nightmare (post-arc). And Nightmare isn’t “+200% health”: it’s better patterns, focus on the vulnerable target and resource management.

06Agents that learn

The bestiary runs on two philosophies. Slimes, rats and low goblins use fixed AI: rules and probability, honest and cheap (“low HP → heal”). Orcs, elementals, dragons and The Architect use trainable AI: nobody hands them the rule “if HP < 20%, heal”. They work it out through reward and punishment, or die trying, millions of times, far from the player’s eyes.

From the NetLogo lab to C#

1. The C# game defines stats, skills and rules.
2. NetLogo, in training mode, runs thousands or millions of battles with no animation.
3. The agent observes a discretised state: HP band, distance, MP, status…
4. ε-greedy: it explores a lot at first, and less and less over time.
5. Updates Q(s,a) ← Q + α [r + γ max Q(s′,a′) − Q].
6. Exports one JSON per species or boss.
7. The PolicyImporter (.NET) picks the action at runtime via argmax or softmax.

The canonical state is the very same string in the simulator and in the game:

• Per-species memory: common goblins share one Q-table, the Goblin King has his own, and every boss carries its own policy.
• Archived self-play: old versions (V1…V10) are kept so the agent doesn’t become an expert at beating only yesterday’s self.
• Curriculum: simple opponent → intermediate → varied classes → equipment → strategies → random combat → opponents that are trained too.
• Weakness pays, resistance costs: in training, exploiting elemental weakness is rewarded. The boss doesn’t need dialogue to look smart; it learned that Fireball on a stone golem is an expensive mistake.

Residents, not just enemies

Darkover doesn’t cheat: it has its own identity and character and runs the loop tick → policy → executor → reward (ΔXP, gold, quests, survival and novelty, minus death). When it finishes the arc it switches to Curiosity mode: the end of the content becomes the start of intelligent wandering.

The Architect

The smartest enemy in the initial system, at level 100: multiple phases, target selection, buffs and debuffs, weaknesses, resource conservation, combos, pattern reactions, summoning and terrain. It was trained against Warrior, Mage, Tank, Healer, Assassin, Archer and Hybrid, not against a single lab build.

07Stack & tooling

The part I’m proudest of is the tooling. Every hero needs gear, so here’s the inventory:

• WMain weaponASP.NET Core MVC 8 · Razor · SignalRWeb layer, with real-time map presence.
• RGrimoireDomainEntities, enums and exceptions: fantasy rules written as code.
• SShieldGameEngineServer-authoritative combat, progression and AI.
• AArmourEF Core · IdentityInfrastructure: persistence, identity, seeding and auditing.
• TArcane tomeNetLogo 6 + table extensionQ-Learning combat training with JSON export.
• ORingPolicyImporterPolicy runtime: argmax or softmax.
• FFamiliarBackgroundServices · Ollama (optional)Agents with persisted policies.
• LLanternCanvas/JS · Web AudioWorld client, with adaptive-quality VFX and prefers-reduced-motion support.

The solution splits into EchoesOfAether.Domain, GameEngine, Application, Infrastructure and Web. The engineering pillars: server authority, readable combat, distributed narrative, two strong identities and extensibility (new classes, areas and chapters without rewriting the engine).

08Dev log & roadmap

Echoes of Aether is in active development. It isn’t a shipped AAA; it’s a vision I can already execute, with lore, simulation and runtime on the same thread. No dates for now: it’s a personal project, and it moves at the Aether’s pace.

Pocket scrolls (project one-liners)