yes, they canjj st!

systems/bullets/behaviors/bullet_behavior.gd

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+@abstract
+class_name BulletBehavior
+extends Resource
+
+
+## Called when a bullet is spawned with this behavior in order to set up
+## behavior-specific state.
+@warning_ignore("unused_parameter")
+func init_bullet(bullet: Bullet) -> void: pass
+
+## Called to process a tick of a bullet's movement.
+@abstract func process_bullet(bullet: Bullet, delta: float) -> void

systems/bullets/behaviors/bullet_behavior.gd.uid

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+uid://djcajenyac4sd

systems/bullets/behaviors/simple_linear_behavior.gd

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+class_name SimpleLinearBehavior
+extends BulletBehavior
+## Makes bullets move in [member Bullet.direction], potentially accelerating.
+
+
+## Initial speed of the bullet when it is spawned.
+@export_custom(0, "suffix:px/s") var initial_speed: float = 0.0
+
+## Rate at which the bullet will speed up.
+@export_custom(0, "suffix:px/s²") var acceleration: float = 0.0
+
+
+func process_bullet(bullet: Bullet, delta: float) -> void:
+	var speed = initial_speed + acceleration * bullet.time_elapsed
+	bullet.position += bullet.direction * speed * delta

systems/bullets/behaviors/simple_linear_behavior.gd.uid

@@ -0,0 +1 @@
+uid://dntp60my5f65m