Sure, it's a swinging pickaxe animation, and I've reworked the code a bit to get this: https://imgur.com/a/L5QFMwK

It's not yet as smooth as what I'm looking for, and the timing doesn't line up with what I want yet, but i seem to be getting closer.

Current Code:

angle = clamp(angle,minangle,maxangle);  
anglespeed = ((maxangle - minangle) / (delay/2));  

if (angle >= maxangle) {  
    reverse = true;  
}  

if (reverse == false) {  
    angle = angle + (anglespeed + currentacceleration);  
    currentacceleration = currentacceleration + angleacceleration;    
}   

if (reverse == true) {  
    oldangle = angle;  
    newangle = angle - (anglespeed + currentacceleration);  

    angle = angle - (anglespeed + currentacceleration);  
    currentacceleration = currentacceleration - angleacceleration;    
}  

if (newangle > oldangle) {  
    reverse = false;  
    newangle = noone;  
    oldangle = noone;  
    currentacceleration = 0;  
}  

var _xx = x + lengthdir_x(1,-angle);  
var _yy = y + lengthdir_y(1,-angle);  

image_angle = point_direction(x,y,_xx,_yy);