Add scaling Alien Grunt boss waves and native simulation; publish Web release

scripts/alien_grunt.gd

@@ -0,0 +1,185 @@
+extends "res://scripts/zombie.gd"
+## One Alien Grunt replaces every tenth wave. Uses the shared office navigation.
+const Hornet = preload("res://scripts/boss_hornet.gd")
+var rank := 1
+var max_hp := 800.0
+var melee_damage := 28.0
+var ranged_damage := 8.0
+var attack_interval := 2.8
+var reward := 1000
+var attack_lock := 0.0
+var pain_cooldown := 0.0
+var model: Node3D
+
+static func stats_for_wave(number: int) -> Dictionary:
+	var grade := maxi(1, floori(number / 10.0))
+	return {
+		"rank": grade, "hp": 800.0 + 400.0 * (grade - 1),
+		"speed": minf(3.4, 2.0 + 0.12 * (grade - 1)),
+		"melee": 28.0 + 6.0 * (grade - 1), "ranged": 8.0 + 2.0 * (grade - 1),
+		"interval": maxf(1.3, 2.8 - 0.18 * (grade - 1)), "reward": grade * 1000,
+	}
+
+func configure(number: int) -> void:
+	var stats := stats_for_wave(number)
+	rank = stats.rank
+	max_hp = stats.hp
+	hp = max_hp
+	speed = stats.speed
+	melee_damage = stats.melee
+	ranged_damage = stats.ranged
+	attack_interval = stats.interval
+	reward = stats.reward
+
+func _ready() -> void:
+	name = "AlienGruntBoss"
+	add_to_group("live_zombies") # bullets, blast, target-counting use the same interface
+	add_to_group("bosses")
+	collision_layer = 0 # no hits or obstruction during materialization
+	collision_mask = 1 | 4
+	var shape := CollisionShape3D.new()
+	var cap := CapsuleShape3D.new()
+	cap.radius = 0.45
+	cap.height = 2.4
+	shape.shape = cap
+	shape.position.y = 1.2
+	add_child(shape)
+	model = preload("res://assets/boss/agrunt_textured.scn").instantiate()
+	model.scale = Vector3.ONE * 1.1
+	add_child(model)
+	anim = model.get_node("AnimationPlayer")
+	for mesh in model.find_children("*", "MeshInstance3D", true, false):
+		mesh.layers = 2
+	for area in model.find_children("*", "Area3D", true, false):
+		area.collision_layer = 0
+		area.collision_mask = 0
+	model.hide()
+	# Residual Xen glow keeps the boss readable after the portal flash has faded.
+	var glow := OmniLight3D.new()
+	glow.name = "XenGlow"
+	glow.light_color = Color(0.5, 1.0, 0.68)
+	glow.light_energy = 0.65
+	glow.light_specular = 0.3
+	glow.omni_range = 3.5
+	glow.shadow_enabled = false
+	glow.position = Vector3(0, 1.8, -1.1)
+	glow.visible = false
+	add_child(glow)
+	cooldown = 0.8
+	_repath = 0
+
+func materialize() -> void:
+	if dead or not is_instance_valid(player) or player.hp <= 0:
+		return
+	model.show()
+	get_node("XenGlow").show()
+	collision_layer = 4
+	entering = false
+	anim.play("threat", 0.1)
+	attack_lock = 0.7
+	Audio.play(self, "agrunt/ag_alert1.wav", true, -8)
+
+func _physics_process(dt: float) -> void:
+	if dead or entering or not is_instance_valid(player) or player.hp <= 0:
+		return
+	cooldown -= dt
+	attack_lock -= dt
+	pain_cooldown -= dt
+	voice_timer -= dt
+	if voice_timer <= 0:
+		voice_timer = 7.0
+		Audio.play(self, "agrunt/ag_idle1.wav", true, -14)
+	var delta := player.global_position - global_position
+	delta.y = 0
+	var distance := delta.length()
+	if distance > 0.01:
+		rotation.y = atan2(-delta.x, -delta.z)
+	var motion := Vector3.ZERO
+	if attack_lock <= 0:
+		if distance <= 2.2 and _attack_clear() and cooldown <= 0:
+			_start_melee()
+		elif distance > 2.2 and distance < 14 and cooldown <= 0 and _ranged_clear():
+			_start_burst()
+		elif distance > 2.0 or not _attack_clear():
+			motion = _pursuit_direction(dt) * speed
+			if motion.length_squared() > 0.01:
+				rotation.y = atan2(-motion.x, -motion.z)
+			if anim.current_animation != "walk":
+				anim.play("walk", 0.12)
+		elif anim.current_animation != "idle1":
+			anim.play("idle1", 0.12)
+	velocity.x = motion.x
+	velocity.z = motion.z
+	velocity.y = -1.0 if is_on_floor() else velocity.y - 20 * dt
+	move_and_slide()
+
+func _ranged_clear() -> bool:
+	var from := global_position + Vector3.UP * 1.5
+	var to := player.global_position + Vector3.UP * 1.0
+	var query := PhysicsRayQueryParameters3D.create(from, to, 1)
+	return get_world_3d().direct_space_state.intersect_ray(query).is_empty()
+
+func _start_melee() -> void:
+	cooldown = attack_interval
+	attack_lock = 0.85
+	anim.play("mattack2", 0.1)
+	Audio.play(self, "agrunt/ag_attack1.wav", true, -9)
+	get_tree().create_timer(0.45).timeout.connect(_attack)
+
+func _attack() -> void:
+	if not dead and not entering and is_instance_valid(player) and player.hp > 0 \
+			and global_position.distance_to(player.global_position) < 2.7 and _attack_clear():
+		player.take_damage(melee_damage)
+
+func _start_burst() -> void:
+	cooldown = attack_interval
+	attack_lock = 0.9
+	anim.play("hornetattack", 0.08)
+	# Telegraph the attack, then fire three visible dodgeable hornets.
+	for i in range(3):
+		get_tree().create_timer(0.3 + i * 0.18).timeout.connect(_fire_hornet)
+
+func _fire_hornet() -> void:
+	if dead or entering or not is_instance_valid(player) or player.hp <= 0:
+		return
+	var from := global_position + Vector3.UP * 1.5
+	var direction := (player.global_position + Vector3.UP - from).normalized()
+	var projectile := Hornet.new()
+	projectile.player = player
+	projectile.shooter = self
+	projectile.damage = ranged_damage
+	projectile.direction = direction
+	get_parent().add_child(projectile)
+	# Begin at the chest, not beyond it: an offset could skip a nearby thin wall.
+	projectile.global_position = from
+	projectile.look_at(projectile.global_position + direction)
+	Audio.play(self, "agrunt/ag_fire1.wav", true, -13)
+
+func take_damage(amount: float, hit_y: float) -> void:
+	if dead or entering or amount <= 0:
+		return
+	var headshot := hit_y - global_position.y > 1.95
+	hp = maxf(0, hp - amount * (1.5 if headshot else 1.0))
+	if hp > 0:
+		if pain_cooldown <= 0:
+			pain_cooldown = 0.7
+			Audio.play(self, "agrunt/ag_pain1.wav", true, -12)
+		return
+	dead = true
+	get_node("XenGlow").hide()
+	remove_from_group("live_zombies")
+	remove_from_group("bosses")
+	add_to_group("boss_corpses")
+	velocity = Vector3.ZERO
+	collision_layer = 0
+	collision_mask = 0
+	for speaker in get_children():
+		if speaker is AudioStreamPlayer3D:
+			speaker.stop()
+			speaker.queue_free()
+	for projectile in get_tree().get_nodes_in_group("boss_projectiles"):
+		if projectile.shooter == self:
+			projectile.queue_free()
+	Audio.play(self, "agrunt/ag_die1.wav", true, -8)
+	anim.play("diehead" if headshot else "diesimple", 0.1)
+	killed.emit(headshot)

scripts/alien_grunt.gd.uid

@@ -0,0 +1 @@
+uid://dgjgrwojm7qea

scripts/boss_hornet.gd

@@ -0,0 +1,55 @@
+extends Node3D
+## Visible, dodgeable Alien Grunt projectile. Swept ray prevents tunnelling.
+const SPEED := 8.0
+const LIFETIME := 3.0
+var direction := Vector3.FORWARD
+var damage := 8.0
+var shooter: CharacterBody3D
+var player: CharacterBody3D
+var age := 0.0
+var spent := false
+
+func _ready() -> void:
+	add_to_group("boss_projectiles")
+	var model: Node3D = preload("res://assets/boss/hornet_textured.scn").instantiate()
+	add_child(model)
+	for area in model.find_children("*", "Area3D", true, false):
+		area.collision_layer = 0
+		area.collision_mask = 0
+	var anim := model.get_node_or_null("AnimationPlayer") as AnimationPlayer
+	if anim != null:
+		# The exported native scene already marks idle as looping.
+		anim.play("idle")
+	var mesh := SphereMesh.new()
+	mesh.radius = 0.055
+	mesh.height = 0.11
+	var glow := StandardMaterial3D.new()
+	glow.shading_mode = BaseMaterial3D.SHADING_MODE_UNSHADED
+	glow.albedo_color = Color(1, 0.7, 0.1)
+	mesh.material = glow
+	var marker := MeshInstance3D.new()
+	marker.mesh = mesh
+	marker.cast_shadow = GeometryInstance3D.SHADOW_CASTING_SETTING_OFF
+	add_child(marker)
+	if direction.length_squared() > 0:
+		look_at(global_position + direction)
+
+func _physics_process(dt: float) -> void:
+	if spent:
+		return
+	age += dt
+	if age >= LIFETIME or not is_instance_valid(shooter) or shooter.dead \
+			or not is_instance_valid(player) or player.hp <= 0:
+		queue_free()
+		return
+	var next := global_position + direction * SPEED * dt
+	var query := PhysicsRayQueryParameters3D.create(global_position, next, 1 | 2)
+	query.exclude = [shooter.get_rid()]
+	var hit := get_world_3d().direct_space_state.intersect_ray(query)
+	if not hit.is_empty():
+		spent = true
+		if hit.collider == player:
+			player.take_damage(damage)
+		queue_free()
+	else:
+		global_position = next

scripts/boss_hornet.gd.uid

@@ -0,0 +1 @@
+uid://0yeh2nqrpj3o

scripts/boss_teleport.gd

@@ -0,0 +1,83 @@
+extends Node3D
+## Cheap Compatibility-safe Xen arrival: rotating rings, CPU wisps, cyan flash.
+signal materialized
+const Audio = preload("res://scripts/hl_audio.gd")
+const ARRIVAL_TIME := 1.5
+var elapsed := 0.0
+var announced := false
+var rings: Array[MeshInstance3D] = []
+var light: OmniLight3D
+
+func _ready() -> void:
+	name = "BossTeleport"
+	Audio.play(self, "ambience/port_suckin1.wav", true, -9)
+	var material := StandardMaterial3D.new()
+	material.shading_mode = BaseMaterial3D.SHADING_MODE_UNSHADED
+	material.transparency = BaseMaterial3D.TRANSPARENCY_ALPHA
+	material.blend_mode = BaseMaterial3D.BLEND_MODE_ADD
+	material.albedo_color = Color(0.12, 1.0, 0.65, 0.8)
+	for i in range(3):
+		var ring := MeshInstance3D.new()
+		ring.cast_shadow = GeometryInstance3D.SHADOW_CASTING_SETTING_OFF
+		var mesh := TorusMesh.new()
+		mesh.inner_radius = 0.91
+		mesh.outer_radius = 1.0
+		mesh.rings = 32
+		mesh.ring_segments = 8
+		mesh.material = material
+		ring.mesh = mesh
+		ring.position.y = 0.10 + i * 0.72
+		add_child(ring)
+		rings.append(ring)
+	light = OmniLight3D.new()
+	light.light_color = Color(0.12, 1.0, 0.65)
+	light.light_energy = 3
+	light.omni_range = 6
+	light.shadow_enabled = false
+	light.position.y = 1.1
+	add_child(light)
+	var particles := CPUParticles3D.new()
+	particles.amount = 40
+	particles.lifetime = 1.0
+	particles.emitting = true
+	particles.emission_shape = CPUParticles3D.EMISSION_SHAPE_SPHERE
+	particles.emission_sphere_radius = 0.9
+	particles.position.y = 0.5
+	particles.direction = Vector3.UP
+	particles.spread = 20
+	particles.initial_velocity_min = 1
+	particles.initial_velocity_max = 2.2
+	particles.gravity = Vector3.ZERO
+	var quad := QuadMesh.new()
+	quad.size = Vector2(0.22, 0.4)
+	var mist := material.duplicate() as StandardMaterial3D
+	mist.billboard_mode = BaseMaterial3D.BILLBOARD_ENABLED
+	mist.albedo_texture = preload("res://assets/effects/flame.png")
+	quad.material = mist
+	particles.mesh = quad
+	var colors := Gradient.new()
+	colors.set_color(0, Color(0.1, 1, 0.65, 0.8))
+	colors.set_color(1, Color(0.05, 0.3, 0.25, 0))
+	particles.color_ramp = colors
+	add_child(particles)
+	get_tree().create_timer(ARRIVAL_TIME).timeout.connect(func():
+		particles.emitting = false)
+
+func _process(dt: float) -> void:
+	elapsed += dt
+	for i in rings.size():
+		var size := maxf(0.05, sin(minf(elapsed / 2.2, 1.0) * PI))
+		rings[i].scale = Vector3.ONE * size * (1.0 + 0.12 * sin(elapsed * 11 + i))
+		rings[i].rotation = Vector3(sin(elapsed * 4 + i) * 0.2, elapsed * 3, 0)
+	light.light_energy = 3 * maxf(0, 1.0 - maxf(0, elapsed - ARRIVAL_TIME) / 0.7)
+	if elapsed >= ARRIVAL_TIME and not announced:
+		announced = true
+		Audio.play(self, "ambience/port_suckout1.wav", true, -9)
+		materialized.emit()
+	if elapsed >= 2.2:
+		# Sound players belong to this node; leave them time to finish.
+		for ring in rings:
+			ring.hide()
+		light.hide()
+		set_process(false)
+		get_tree().create_timer(3).timeout.connect(queue_free)

scripts/boss_teleport.gd.uid

@@ -0,0 +1 @@
+uid://h5wtakci76b2

scripts/game_hud.gd

@@ -9,6 +9,9 @@ var wave_value: Label
 var grenade_value: Label
 var help: Label
 var root: Control
+var boss_panel: VBoxContainer
+var boss_name: Label
+var boss_health: ProgressBar
 
 func _ready() -> void:
 	layer = 2
@@ -44,6 +47,31 @@ func _ready() -> void:
 	help.offset_right = 420
 	help.offset_top = -30
 	help.offset_bottom = -8
+	boss_panel = VBoxContainer.new()
+	boss_panel.mouse_filter = Control.MOUSE_FILTER_IGNORE
+	root.add_child(boss_panel)
+	boss_panel.set_anchors_and_offsets_preset(Control.PRESET_CENTER_TOP)
+	boss_panel.offset_left = -180
+	boss_panel.offset_right = 180
+	boss_panel.offset_top = 76
+	boss_name = _label(boss_panel, "ALIEN GRUNT", 17, Vector2.ZERO)
+	boss_name.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
+	boss_health = ProgressBar.new()
+	boss_health.mouse_filter = Control.MOUSE_FILTER_IGNORE
+	boss_health.custom_minimum_size = Vector2(360, 18)
+	boss_health.show_percentage = false
+	boss_health.step = 0.0 # explosion falloff produces fractional health values
+	boss_health.rounded = false
+	var fill := StyleBoxFlat.new()
+	fill.bg_color = Color(0.14, 0.85, 0.5)
+	boss_health.add_theme_stylebox_override("fill", fill)
+	var background := StyleBoxFlat.new()
+	background.bg_color = Color(0.02, 0.05, 0.03, 0.9)
+	background.border_color = AMBER
+	background.set_border_width_all(1)
+	boss_health.add_theme_stylebox_override("background", background)
+	boss_panel.add_child(boss_health)
+	boss_panel.hide()
 
 func _panel(label: String, right: bool) -> Panel:
 	var panel := Panel.new()
@@ -76,6 +104,15 @@ func _label(parent: Control, text: String, size: int, pos: Vector2) -> Label:
 	parent.add_child(label)
 	return label
 
+func update_boss(boss: Node) -> void:
+	boss_panel.visible = is_instance_valid(boss) and not boss.dead
+	if not boss_panel.visible:
+		return
+	boss_name.text = "ALIEN GRUNT — GRADO %d%s" % [boss.rank,
+		" — ARRIVO" if boss.entering else "  |  %d / %d" % [ceili(boss.hp), ceili(boss.max_hp)]]
+	boss_health.max_value = boss.max_hp
+	boss_health.value = boss.hp
+
 func update_status(player: Node, wave: int, score: int) -> void:
 	health_value.text = str(maxi(0, ceili(player.hp)))
 	health_value.add_theme_color_override("font_color", DANGER if player.hp <= 25 else AMBER)

scripts/main.gd

@@ -1,6 +1,8 @@
 extends Node3D
 const PlayerScript = preload("res://scripts/player.gd")
 const ZombieScript = preload("res://scripts/zombie.gd")
+const BossScript = preload("res://scripts/alien_grunt.gd")
+const BossTeleport = preload("res://scripts/boss_teleport.gd")
 const RoomScript = preload("res://scripts/room.gd")
 const LeaderboardScript = preload("res://scripts/leaderboard.gd")
 const StartScreenScript = preload("res://scripts/start_screen.gd")
@@ -26,15 +28,28 @@ var leaderboard: Node
 var start_screen: CanvasLayer
 var profile := {}
 var score_submitted := false
+var boss: CharacterBody3D
+var boss_simulation := false
+var simulation_wave := 0
+var simulation_god := false
+var simulation_finished := false
+var simulation_restarting := false
+var simulation_label: Label
+var simulation_retry: Button
 
 func _ready() -> void:
 	smoke = "--smoke" in OS.get_cmdline_user_args()
-	profile = Profile.load_profile()
+	if not _configure_simulation():
+		return
+	# A simulation must never read/write the real player's profile or public scores.
+	profile = {"name": "SIMULAZIONE", "player_id": "boss-simulation", "best": 0} \
+		if boss_simulation else Profile.load_profile()
 	room = Node3D.new()
 	room.set_script(RoomScript)
 	add_child(room)
 	player = CharacterBody3D.new()
 	player.set_script(PlayerScript)
+	player.invulnerable = boss_simulation and simulation_god
 	player.position = Vector3(0, 0.1, 0)
 	add_child(player)
 	var envnode := WorldEnvironment.new()
@@ -89,6 +104,12 @@ func _ready() -> void:
 	leaderboard.score_submitted.connect(_on_score_submitted)
 	leaderboard.submit_failed.connect(_on_submit_failed)
 	player.died.connect(_on_player_died)
+	if boss_simulation:
+		leaderboard.disabled = true
+		leaderboard.base_url = ""
+		_setup_simulation_ui()
+		call_deferred("_start_simulation")
+		return
 	start_screen = CanvasLayer.new()
 	start_screen.set_script(StartScreenScript)
 	start_screen.player = player
@@ -112,7 +133,7 @@ func _on_start_pressed(player_name: String) -> void:
 
 func start_game(player_name: String, save_profile := true) -> void:
 	profile["name"] = player_name
-	if save_profile:
+	if save_profile and not boss_simulation:
 		Profile.save_profile(profile)
 	if not player.touch_mode:
 		Input.mouse_mode = Input.MOUSE_MODE_CAPTURED
@@ -126,6 +147,11 @@ func start_game(player_name: String, save_profile := true) -> void:
 
 ## Alla morte si invia UNA volta il punteggio finale con nome e id del giocatore.
 func _on_player_died() -> void:
+	if boss_simulation:
+		simulation_finished = false
+		simulation_retry.hide()
+		player.set_death_note("SIMULAZIONE — R / RICOMINCIA per riprovare; nessun punteggio inviato")
+		return
 	if score_submitted:
 		return
 	score_submitted = true
@@ -199,9 +225,13 @@ func _restart_music() -> void:
 func _process(_dt: float) -> void:
 	if hud:
 		hud.update_status(player, wave, score)
+		hud.update_boss(boss)
+
+static func is_boss_wave(number: int) -> bool:
+	return number > 0 and number % 10 == 0
 
 func zombies_for_wave(number: int) -> int:
-	return 4 + number * 2
+	return 0 if is_boss_wave(number) else 4 + number * 2
 
 func _next_wave() -> void:
 	wave_pending = false
@@ -209,6 +239,12 @@ func _next_wave() -> void:
 		return
 	wave += 1
 	spawning = true
+	if is_boss_wave(wave):
+		_spawn_boss()
+		spawning = false
+		_check_wave()
+		return
+	boss = null
 	for i in zombies_for_wave(wave):
 		if player.hp <= 0:
 			break
@@ -265,4 +301,110 @@ func _spawn() -> void:
 func _check_wave() -> void:
 	if alive == 0 and not spawning and not wave_pending and player.hp > 0:
 		wave_pending = true
+		if boss_simulation:
+			simulation_finished = true
+			simulation_label.text = "BOSS SCONFITTO — ondata %d | R o RIPROVA per ricominciare" % wave
+			simulation_retry.show()
+			Input.mouse_mode = Input.MOUSE_MODE_VISIBLE
+			return
 		get_tree().create_timer(3).timeout.connect(_next_wave)
+
+func _boss_spawn_position() -> Vector3:
+	var candidates := [Vector3(0, 0.05, -6), Vector3(6, 0.05, 0),
+		Vector3(0, 0.05, 6), Vector3(-6, 0.05, 0), Vector3(6, 0.05, 6),
+		Vector3(-6, 0.05, -6), Vector3(6, 0.05, -6), Vector3(-6, 0.05, 6)]
+	candidates.shuffle()
+	var capsule := CapsuleShape3D.new()
+	capsule.radius = 0.5
+	capsule.height = 2.5
+	for candidate: Vector3 in candidates:
+		if candidate.distance_to(player.global_position) < 5:
+			continue
+		var query := PhysicsShapeQueryParameters3D.new()
+		query.shape = capsule
+		query.transform = Transform3D(Basis.IDENTITY, candidate + Vector3.UP * 1.25)
+		query.collision_mask = 1 | 2 | 4
+		if get_world_3d().direct_space_state.intersect_shape(query, 1).is_empty() \
+				and navigation.route(candidate, player.global_position).size() > 1:
+			return candidate
+	# Fixed office layout has clear candidates; never silently spawn inside a prop.
+	return Vector3.INF
+
+func _spawn_boss() -> void:
+	var at := _boss_spawn_position()
+	if not at.is_finite():
+		push_error("Nessun punto libero per il boss")
+		return
+	boss = BossScript.new()
+	boss.configure(wave)
+	boss.player = player
+	boss.navigation = navigation
+	boss.position = at
+	var instance := boss
+	alive += 1
+	boss.killed.connect(func(_headshot: bool):
+		score += instance.reward
+		alive -= 1
+		_check_wave())
+	add_child(boss)
+	var portal := BossTeleport.new()
+	portal.position = at
+	portal.materialized.connect(func():
+		if is_instance_valid(instance):
+			instance.materialize())
+	add_child(portal)
+
+func _configure_simulation() -> bool:
+	if OS.has_feature("web"):
+		return true
+	for argument in OS.get_cmdline_user_args():
+		if argument.begins_with("--boss-wave="):
+			var value := argument.substr(12)
+			if not value.is_valid_int() or not is_boss_wave(int(value)):
+				push_error("--boss-wave richiede un multiplo positivo di 10: 10, 20, 30...")
+				get_tree().quit(2)
+				return false
+			simulation_wave = int(value)
+			boss_simulation = true
+	simulation_god = "--boss-god" in OS.get_cmdline_user_args()
+	return true
+
+func _start_simulation() -> void:
+	# Wait for static physics shapes/navigation to be registered before choosing a portal.
+	await get_tree().physics_frame
+	wave = simulation_wave - 1
+	start_game("SIMULAZIONE", false)
+	print("BOSS SIMULATION: wave=", simulation_wave, " god=", simulation_god,
+		" | public scores/profile writes disabled")
+
+func _setup_simulation_ui() -> void:
+	var canvas := CanvasLayer.new()
+	canvas.layer = 6
+	add_child(canvas)
+	simulation_label = Label.new()
+	simulation_label.text = "SIMULAZIONE BOSS — ONDATA %d%s | nessun punteggio online" % [
+		simulation_wave, " | INVULNERABILE" if simulation_god else ""]
+	simulation_label.position = Vector2(18, 125)
+	simulation_label.add_theme_font_size_override("font_size", 18)
+	simulation_label.add_theme_color_override("font_color", Color(0.2, 1, 0.7))
+	simulation_label.mouse_filter = Control.MOUSE_FILTER_IGNORE
+	canvas.add_child(simulation_label)
+	simulation_retry = Button.new()
+	simulation_retry.text = "RIPROVA IL BOSS"
+	simulation_retry.position = Vector2(510, 520)
+	simulation_retry.size = Vector2(260, 60)
+	simulation_retry.pressed.connect(_restart_simulation)
+	simulation_retry.hide()
+	canvas.add_child(simulation_retry)
+
+func _input(event: InputEvent) -> void:
+	# Only the completed native simulation has this shortcut. No menu click-to-start.
+	if boss_simulation and simulation_finished and event.is_action_pressed("reload"):
+		get_viewport().set_input_as_handled()
+		_restart_simulation()
+
+func _restart_simulation() -> void:
+	if simulation_restarting:
+		return
+	simulation_restarting = true
+	get_tree().reload_current_scene()

scripts/player.gd

@@ -6,6 +6,7 @@ var damage_feedback: CanvasLayer
 const DamageFeedback = preload("res://scripts/damage_feedback.gd")
 const MAX_HP := 100.0
 var hp := MAX_HP
+var invulnerable := false # only enabled by the explicit native boss simulation flag
 var _regen_elapsed := 0.0
 
 ## Discreto: +1 HP per secondo di gioco, mai oltre il massimo o dopo morte.
@@ -215,7 +216,7 @@ func throw_grenade() -> RigidBody3D:
 	return grenade
 
 func take_damage(amount: float) -> void:
-	if death_started or amount <= 0:
+	if death_started or invulnerable or amount <= 0:
 		return
 	hp = maxf(0, hp - amount)
 	if hp <= 0: