Action2/Only Callback Failure

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The features

  • Sound Effects
  • Signals

have no regular Action2 to assign graphics. However, Action2 is still needed to make callbacks fail.


<Sprite-number> * <Length> 01 <feature> 01 00
<Sprite-number> * <Length> 02 <feature> <set-id> 01 00 00 00

This syntax consists of both an Action1 and the actual Action2. See the detailed description below.

Element Size Description
<Sprite-number> dec A sequential sprite number
<length> dec The total number of bytes used in this action
<set-id> B What set-ID this action2 defines


The syntax to use is the syntax of the regular Action2 referencing Action1 spritesets. However:

  • Every Action2 must reference at least one spriteset, so we must also define one via Action1.
  • Every Action1 must define at least one spriteset, but spritesets may contain zero sprites.

Above syntax specifies two pseudo sprites. First an Action1 defining 1 spriteset with 0 sprites, then the Action2 referencing only that single spriteset.


This is just the number you are at.


Count the number of bytes in this action.


This defines the ID of the current action 2. This ID will later be referred to by action 3, or a variational/random action 2.

You can reuse action 2 IDs, and there's no restriction on the order in which they are defined.