User blog comment:Kogath/Monster Hunter 4 Ultimate for the Nintendo 3DS/@comment-184612-20140723233043/@comment-6050823-20140724200644

Minor Notes On MH4G
 * The Heavy Bowgun can now hold to a Wyvernfire shot, which you can use at anytime, while also using other ammo/shots.
 * Dual Blades now a spin attack while in Demon Mode, which does more damage than that two hit combo.
 * Some monsters in the Old Desert only appear at night and some of the areas in the Old Desert change in someway at night.
 * Charge Blade receives some changes though was already explained by Kogath.
 * Diablos is a lot more destructive and willing to break through all sorts of obstacles to get to hunters, same goes for Black Diablos.
 * From the look of one scan, it seems Black Diablos now roars when it spots a hunter.