Many changes

Handle it

player/modifiers/projectile_size_multiplicative.gd

@@ -0,0 +1,14 @@
+class_name ProjectileSizeMultiplicative extends Modifier
+
+@export var size_multiplier: float = 1.5 # 50% bigger
+
+func _init():
+    id = "size_multiplicative"
+    display_name = "Giant Projectiles"
+    description = "Multiplies projectile size by %0.1fx" % size_multiplier
+    modifier_type = ModifierType.MULTIPLICATIVE
+    priority = 10 # Higher priority than the additive version
+
+func apply_stats_modification(final_stats: Dictionary, base_stats: Dictionary) -> void:
+    if final_stats.has("projectile_size"):
+        final_stats.projectile_size *= size_multiplier