We know that the Great Weapon Fighting fighting style allows the rerolling of all 1 and 2s that come from a weapon taking the new roll.
If a player using a Greatsword gets a critical hit and rolls 4d6 damage, does the GWF count for all 4d6, or just the underlying 2d6?
Does a Half-Orc get to apply GWF to their Savage Attacks, allowing a potential 5d6 under the GWF rule to be rerolled on 1 and 2's?