pass OnSliderChange value to function?

Why is there even a changed event on sliders if it doesn’t pass it’s value? Do I have to make an object reference to it to use it?

You don’t have to make a Slider mySlider type Object reference to use it. If you define a method in your class that has float as parameter, then you can drop the class reference into the slider widget and on the dropdown under ‘dynamic floats’ you’ll see the (public) method shown.