woopsies! there's a typo. in the instance_create, you accidentally put player.x instead of objPlayer.x
typos can get you, man!
P.S. any variables which are defined with var; code will disappear after the code ends, but if you drop the var; part and just define the variable then it'll stay permanent throughout the object.
P.S.S. making it happen 5 times can be done with a variable.
In the create event: amount=0;
In the alarm event:
if amount<5{
amount+=1;
alarm[0]=100;
if instance_exists(objPlayer){
var a = instance_create(objPlayer.x,y,objGLSword);
}
}
and whenever you want the attack to happen again, just reset amount to 0.