- What would you like to request: I want a behavior resembling the charged shots from Mega Man 3 and onward. By holding down and then releasing B, Mega Man can increase the power of his Mega Buster shots and a few Special Weapons.
- Why you are requesting it: To save time and effort programming three charge levels of a Mega Buster shot.
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Thanks. 
Hello!
While I don’t see any issue that would stop someone from making this an extension, please note that it is unlikely to take any less time to use than the usual way you would do a charge shot:
Event that starts a timer once the shot button is pressed. (With trigger once)
Event that checks if the shot button is released, with 3 sub Events that check if the timer is greater than X but less than y for each charge level, and then fires the appropriate shot type and pauses the timer.
Even with an extension you are going to have roughly the same amount of events since you’d not be able to incorporate all of the above into less events.