How to Create a Score System

Create a ScoreManager autoload (singleton). Go to Project → Autoload, create 'ScoreManager.gd'. Add variables: `var current_score = 0`, `var high_score = 0`, `var combo = 0`, `var combo_multiplier = 1.0`. Add signals: `signal score_updated(score)`, `signal high_score_changed(high_score)`.

Create add_score function: `func add_score(points):`, `var total_points = int(points * combo_multiplier)`, `current_score += total_points`, `score_updated.emit(current_score)`. Add combo system: `func add_combo(): combo += 1`, `combo_multiplier = 1.0 + (combo * 0.1)` (10% increase per combo).

Reset combo on mistake or timeout: `func reset_combo(): combo = 0`, `combo_multiplier = 1.0`. Add a timer: `var combo_timer = Timer()`, `combo_timer.wait_time = 3.0`, `combo_timer.timeout.connect(reset_combo)`, `add_child(combo_timer)`. Call `combo_timer.start()` when combo increases to reset if player doesn't continue actions.

Display score in HUD. Create HUD scene with Labels: `@onready var score_label = $ScoreLabel`, `@onready var combo_label = $ComboLabel`. Connect signals: `ScoreManager.score_updated.connect(_on_score_updated)`. Update functions: `func _on_score_updated(score): score_label.text = 'Score: ' + str(score)`.

Save and load high score. In ScoreManager `_ready()`: Load saved high score: `if FileAccess.file_exists('user://highscore.save'): var file = FileAccess.open('user://highscore.save', FileAccess.READ)`, `high_score = int(file.get_line())`. When current_score beats high_score: `if current_score > high_score: high_score = current_score`, `save_high_score()`. Save function: `var file = FileAccess.open('user://highscore.save', FileAccess.WRITE)`, `file.store_line(str(high_score))`.