Broadcasts indicate that something has happened, similiar to what variables do. You can have one sprite broadcast something when a player dies and another sprite receiving the broadcast and then doing it's action.
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For Example:
Sprite A
When Green flag clicked
Forever
If touching color 'blue'
broadcast [touching blue]
Sprite B
When I receive [touching blue]
Go to x [0], y [0]
Switch to costume [costume 2]
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