I've created a GMK tutorial for those that need help showing a boost effect in a Sonic game. Everything's explained in the Game Information (shortcut to that is F1) and object Sonic's events (via comments. Copyable GML is now provided). Please comment about further help or advice.
Edit: May 19, 2013 - 4th Version available

Tags: sonic, the, hedgehog, boost, tutorial, lightdasher, lighdasher360, open, source

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