Phaser 3 → Phaser 4 Migration

Migrating from Phaser 3 to Phaser 4 is mostly straightforward. The core public API is preserved. This skill covers every breaking change and how to fix it — AND also covers moving between Phaser 4 point releases (4.0 → 4.1 → 4.2), plus the runtime behaviour that compiles cleanly and still surprises you.

Step 1 — Update the Package

npm uninstall phaser
npm install phaser

Verify installed version:

node -e "const p = require('phaser'); console.log(p.VERSION)"

Should print 4.2.1 (or later RC).

Step 2 — Scan for Breaking Changes