SyphonGames

Acheron: a guide to your first escape

Updated 16 October 2026

Acheron is a game about getting out of the Underverse, and you will not manage it on the first try. That is the point: every run sends you home stronger. This guide explains what each part of a run is for, so the early deaths teach you something.

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Undertow Station, the hub between runs, where Nyra, Keeper of the Station, greets the runner as they wake.
Acheron on SyphonGames.

How a run works

You start at Undertow Station and fight upwards through four regions, room by room. Clear a room and the doors open, each one showing the reward waiting behind it, so every door is a choice. Each region has a mini-boss along the way and a boss at the end. When you fall, the river carries you back to the Station with whatever you collected that lasts between runs. A full escape takes twenty to forty minutes.

Staying alive

  • Dash through attacks, not away from them. You cannot be hurt mid-dash (Space or Shift), so dashing through a swing or a shockwave ring is often safer than backing off.
  • Read the floor. Red shapes show where an attack is about to land. Move out of them before they fill.
  • Save your Call. The Call (F) is a big Signal-powered move that needs a full gauge. It is the answer to a bad room or a boss phase, not a way to open a fight.
  • Use your Cast. Q throws your Cast, which your boons will soon turn into something nasty.
  • Kill the support first. Some foes protect others. A siren's song coats her friends in shells of light, so silence her first.

The six weapons

Each weapon has an Attack (left click or J) and a Special (right click or K). You start with the Arc Blade and unlock the others with Keys.

  • Arc Blade (free): a fast three-hit combo, and a Special that slams the floor around you. Forgiving, and the weapon to learn the game with.
  • Volt Spear (1 Key): long reach. Hold Attack to spin; the Special throws the spear and calls it back.
  • Bulwark (2 Keys): bash and block. Hold Attack to guard and charge a rush; the Special throws the shield.
  • Prism Bow (3 Keys): hold Attack to charge and release at the flash for a Power Shot; the Special fires a volley.
  • Pulse Fists (4 Keys): a flurry of jabs, with a rising uppercut Special you can chain twice.
  • Rail Cannon (5 Keys): hold Attack to fire, then reload with R; the Special lobs a bomb wherever you aim.

Prisms awaken each weapon's aspects, alternative versions that change how it plays.

The eight Signals

Signals drift down from the surface and offer boons: blessings that change your Attack, Special, Cast, Dash and Call for the rest of the run. Each Signal has a style, and a run usually comes together around one or two of them.

  • Volta, the Storm: lightning that leaps from foe to foe.
  • Cryo, the Long Cold: Chill that slows foes, then shatters them.
  • Pyra, the Furnace: fire that keeps on hurting.
  • Venin, the Green Rot: poison that stacks and ruptures.
  • Hex, Ill Omens: Doom, curses that burst a moment later.
  • Aegis, the Bright Wall: deflection, shields and second chances.
  • Gale, the High Wind: speed, dodges and foes hurled into walls.
  • Umbra, the Unlit Moon: critical hits and attacks from behind.

There are ninety-four boons in all. When you hold boons from two Signals that work together, a Duo boon can appear, such as lightning that chills what it strikes, or Doom that can land critical hits. Aim for one main Signal for your Attack and Special, and pick up a second for the Duo.

What the doors offer

Some rewards help this run only; others come home with you.

  • For this run: a new boon, a level-up for a boon you already have, a weapon upgrade, healing, and Chits, which the Ferryman takes in exchange for goods in the rooms where he turns up.
  • Echoes are what is left of every foe you fell. Spend them at the Mirror on permanent talents.
  • Keys unlock new weapons and the Mirror's locked rows.
  • Shards are building material: Rook uses them for Station works.
  • Glow is warm light in a bottle, a gift for the people at the Station.
  • Prisms awaken and strengthen weapon aspects.

Early on, Echoes and Keys are worth more than they look: Mirror talents such as extra health on entering a room or a Second Chance make every later run easier.

The four regions

  • The Drowned Grid: a flooded server-city where the dead are filed and forgotten. The Doorwarden guards the middle, and Sister Static, Keeper of the Grid, waits at the end.
  • The Cobalt Floodworks: pumps and locks holding back an ocean of memory. The Tidecaller, Queen of the Sirens, raises the water in rings; the Leviathan Engine, a pump the size of a cathedral, is the region's heart.
  • The Ember Arcade: a midway built over a furnace. The Ringmaster spins fire on spokes, and the champions Brand and Gleam fight as a tag team: Brand charges, Gleam throws spears of light from behind a mirror shield.
  • The Aether Spire: the tower that holds the lid on the Underverse. The Archon's six orbiting swords guard the climb, and at the top is the Warden, Lord of the Underverse. Above him, the dawn.

Undertow Station

Between runs you are home, and the people there have something new to say after almost every attempt. Nyra runs the Station and found you on the platform when you were small. Dusk, a retired Arcade champion, teaches you to fight. Cassia catches the Signals on the radio desk. Rook guards the gate and approves Station works, from a training dummy that shows your damage to new chances for Trial rooms and quiet rooms where you might meet Moth. The Ferryman sells things in rooms where nobody should be selling anything. Giving Glow raises your affinity with each of them.

The Static Pact

Escape once and the Static Pact opens. It lets you make the next run harder, with foes that hit harder, weaker healing, a time limit on each region and more, in exchange for bigger rewards. Add a little Static at a time; a run with too much is over in the first region.

Controls

WASD to move, left click or J to attack (hold to charge or keep firing), right click or K for your Special, Space or Shift to dash, Q to Cast and F to Call. E talks and interacts, Tab shows your boons and Esc pauses. A gamepad works, and on a phone the left thumb moves with the buttons on the right. Progress is saved in your browser.

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