Don’t double post. Review the forum rules.
For the charge shot, I would do something like this pseudo-code for your character object:
Object creation:
create a variable “chargeTimer”, set it to 0.
Each step:
if (fire key is pressed) fire a normal shot.
if (fire key is being held) add 1 to chargeTimer.
otherwise
{
if (chargeTimer is greater than, say, 45) fire a charged shot.
set chargeTimer back to 0.
}
To add graphics or sound to it, the main part is just determining whether a shot is being charged or not. With the above code, that would be when chargeTimer is greater than some low value like 10.
You’ll probably want to look up more info about the language you’re working with to get the above pseudo-code translated. If it’s Game Maker, then the help library is what you’ll use.