Icebox Coffin Bat Fx

Based on game build 714014 | Last updated: 2026-03-05

Overview

icebox_coffin_bat_fx is a lightweight FX prefab that spawns a temporary, non-persistent visual effect representing a bat exiting from a coffin in the Icebox biome. It is designed to run only on the client side (excludes dedicated servers), and does not participate in world simulation or persistence. The prefab uses proxy data (specifically a variation property) to determine which of three bat animations to play and plays randomized fluttering sound effects during playback.

It does not add any custom components or define logic beyond entity creation and basic setup; its functionality is almost entirely contained in the top-level fn() constructor and two helper functions.

Usage example

This prefab is instantiated internally by the game when a specific in-world event occurs (e.g., opening an icebox_coffin). Modders typically do not instantiate it directly.

However, a typical call flow looks like this:

-- Internal usage by the game (simplified pseudo-code)
local fx = SpawnPrefab("icebox_coffin_bat_fx")
fx.variation:set(math.random(3))  -- client-side variation is set on master

Dependencies & tags

Components used: None (uses only built-in entity components: transform, animstate, soundemitter, network).
Tags: Adds FX and NOCLICK to spawned FX entities; FX to the root entity.

Properties

Property	Type	Default Value	Description
variation	net_tinybyte	nil	Networked property (client-server synced) indicating which bat animation variant to play (0, 1, or 2). Set only on the master instance and replicated to clients.

Main functions

DoFlutterSound(inst, intensity)

• Description: Recursively plays the bat flap sound using easing.outQuad() to modulate volume (intensity) and continues scheduling future sound events as intensity decays.
• Parameters:
  • inst (Entity) — the entity playing the sound.
  • intensity (number) — initial sound volume/intensity (must be <= 1.0).
• Returns: Nothing.
• Error states: recursion terminates when intensity <= 0.12.

PlayBatFX(proxy)

• Description: Creates and configures a local-only entity with animation, sound, and lifetime logic to render the bat FX. Only runs on non-dedicated clients.
• Parameters:
  • proxy (Entity) — the source entity from which this FX inherits transform and variation data.
• Returns: Nothing.
• Error states: No effect if proxy.variation:value() <= 0.

fn()

• Description: Constructor function that creates the root FX entity. Sets up network replication, spawns the client-side FX via PlayBatFX, and ensures the entity is removed after 1 second on the master sim.
• Parameters: None.
• Returns: (Entity) the fully configured FX prefab instance.

Events & listeners

• Listens to: animover — removes the FX entity when its animation completes.
• Pushes: None.