---
title: "Run Progression: API"
package: "@phaser-ae/run-progression"
tier: Pro
version: 3.0.0-2
released: 2026-10-14
updated: 2026-10-19
description: "The meta-game of a roguelike run, with a seeded branching map to a boss, reward drafts, shops, weapon evolutions and unlocks that outlive each run."
url: https://phaser.io/packs/run-progression/api
site: Phaser - https://phaser.io
---

# Run Progression: API

`@phaser-ae/run-progression` — Seeded branching runs, reward drafts, shops, weapon evolution and persistent unlocks.

## The pack

### `runProgression`

```ts
function runProgression():Pack<{runProgression:typeof rules}>
```

Install renderer-independent run progression policies.

## Helpers

### `availableUpgrades`

```ts
function availableUpgrades(defs: readonly Upgrade[], levels: Readonly<Record<string, number>>): Upgrade[]
```

The upgrades that can be taken at these levels: below their max level, with prerequisites met and not replaced by one already held.

### `createRun`

```ts
function createRun(seed = 0, difficulty: Difficulty = 'medium', definitions: readonly Upgrade[] = actionUpgrades, profile?: Profile)
```

Start a run with a seed (default 0), difficulty (default `medium`), upgrade definitions (default `actionUpgrades`) and an optional profile. Throws on invalid definitions or seed.

### `draftUpgrades`

```ts
function draftUpgrades(defs: readonly Upgrade[], levels: Readonly<Record<string, number>>, seed: number, count = 3): string[]
```

Stable without replacement draft. Evolution definitions use requirements and replaced weapon IDs.

### `generateRunMap`

```ts
function generateRunMap(seed: number, difficulty: Difficulty = 'medium'): RunMap
```

Generate varied, reachable DAGs; every offered route reaches a boss and every node is reachable.

## Classes

### `RunProgression`

```ts
class RunProgression
```

A branching run: a seeded map of encounters, reward drafts, shops, upgrades and a persistent profile.

- `readonly definitions: Upgrade[]` — The upgrade definitions, a copy of those passed in.
- `state: RunState` — The run's plain-data state; `snapshot()` copies it.
- `constructor(seed = 0, difficulty: Difficulty = 'medium', definitions: readonly Upgrade[] = actionUpgrades, profile: Profile = { unlocks: [], completedRuns: 0 })`
- `node()` — The node the run is at.
- `finish(reward = 10)` — Finish the current encounter: pay `reward` credits (default 10) and offer a draft, or win the run at the boss. Returns false when it was already finished or the run is over. Throws unless `reward` is a whole number, 0 or more.
- `offer()` — The draft on offer: up to 3 upgrade ids. One is made if none is pending, then the same ids are returned until one is chosen.
- `choose(id: string)` — Take an offered upgrade and clear the draft. Returns false when `id` is not on offer.
- `buy(id: string)` — Buy an upgrade at a shop for its price. Returns false unless the run is at a shop with credits enough, the upgrade is available and not already bought there, and the run is not over.
- `travel(id: string)` — Move to the connected node `id`. Returns false unless this encounter is finished, no draft is pending, `id` is one of the node's `next` and the run is not over.
- `fail()` — End the run as lost, and drop any draft on offer. Does nothing once the run is won.
- `restart()` — Start a new run on the same seed and difficulty, keeping the profile.
- `newRun(seed: number, difficulty = this.state.map.difficulty)` — Start a new run on `seed` (difficulty defaults to the current one), keeping the profile and the definitions. Throws unless the seed is an unsigned 32-bit whole number.
- `snapshot()` — A plain copy of the run state.
- `restore(s: RunState)` — Load a snapshot. Throws when its version is not 1, its map does not match its seed and difficulty, it names an unknown node or upgrade, a level is out of range, a number is not a whole number or a draft entry is not available.

## Constants

### `actionUpgrades`

```ts
const actionUpgrades: Upgrade[]
```

The built-in upgrade set: bolt, haste, multishot, vitality and magnet, and Star nova, which evolves from bolt 3 with haste 1 and replaces bolt.

## Types

### `Profile`

```ts
interface Profile
```

What outlives a run: carried into the next by `restart` and `newRun`.

- `unlocks: string[]` — Ids of unlocks earned; `veteran` is added on the first boss win.
- `completedRuns: number` — Runs won so far.

### `RunMap`

```ts
interface RunMap
```

A generated run map: a graph of encounters, column by column, from a start to a boss.

- `seed: number` — The seed the map was generated from; the same seed and difficulty give the same map.
- `difficulty: Difficulty` — The difficulty the map was generated for; harder maps are deeper.
- `nodes: RunNode[]` — Every node, in column order.
- `start: string` — Id of the first node.

### `RunNode`

```ts
interface RunNode
```

One encounter on the run map.

- `id: string` — Unique id of the form `depth:lane`.
- `depth: number` — Column of the node along the run, 0 at the start; the last column is the boss.
- `lane: number` — Row of the node within its column, 0 at the top.
- `kind: 'fight' | 'elite' | 'rest' | 'shop' | 'boss'` — What the node is: a fight, an elite fight, a rest, a shop or the boss.
- `next: string[]` — Ids of the nodes the run can travel to from here, in the next column.
- `seed: number` — Unsigned 32-bit seed for the game to build this node's encounter from.

### `RunState`

```ts
interface RunState
```

The whole run as plain data, for saving.

- `version: 1` — The snapshot format; always 1.
- `map: RunMap` — The map the run is on.
- `current: string` — Id of the node the run is at.
- `cleared: string[]` — Ids of the nodes whose encounters have been finished.
- `credits: number` — Credits held, from finished encounters; shops spend them.
- `upgrades: Record<string, number>` — Level held of each upgrade, by id; upgrades not held are absent.
- `draft: string[]` — Ids of the upgrades on offer now; empty when none is pending.
- `draftIndex: number` — How many drafts have been offered; it varies the seed of the next one.
- `shopBought: string[]` — Purchases made, as `nodeId/upgradeId`, so a shop sells each upgrade once.
- `won: boolean` — Whether the boss has been cleared.
- `lost: boolean` — Whether the run has been lost.
- `profile: Profile` — The persistent profile carried between runs.

### `Upgrade`

```ts
interface Upgrade
```

An upgrade a run can offer or sell.

- `id: string` — Unique, non-empty id.
- `name: string` — The name shown to the player.
- `maxLevel: number` — Highest level it can reach; a whole number, 1 or more.
- `price: number` — Price in credits at a shop; a whole number, 0 or more.
- `requires: Record<string, number>` — Prerequisites as upgrade id to the minimum level that must be held first.
- `replaces: string[]` — Ids of upgrades removed when this one is taken (an evolution replaces its base weapon), which can then not be offered again.

---

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