Preheat your oven to 350°F (175°C).
In a medium bowl, whisk together the flour, baking soda, and salt.
In a large mixing bowl, beat the room temperature butter, brown sugar, and regular sugar using an electric mixer until light and fluffy, about 2-3 minutes.
Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract until fully combined.
Gradually add the dry ingredients to the wet mixture, mixing on low speed until just combined. Be careful not to overmix.
Fold in the oats, butterscotch chips, white chocolate chips, and semi-sweet chocolate chips using a spatula or wooden spoon.
Using a cookie scoop or spoon, drop rounded tablespoons of dough onto the prepared baking sheet, leaving space between each cookie.
Bake in the preheated oven for 10-12 minutes, or until the edges are golden brown but the centers are still soft.
Allow the cookies to cool on the baking sheet for about 5 minutes before transferring to a wire rack to cool completely.