Gold and GP for Global Strike.
Gold and GP can be used to purchase powerful and recommended weapons, characters and items. By using the gold, you can own several permanent weapons including the Dual Blue Devil, AR15-S, Colored Deagle, Dual Batons, Flame Slingshot, and Gatling Gun Silver to do tons of damage. It can also be used to purchase Blue Crystals and Yellow Crystals to unlock the Elite Arsenal and the Golden Arsenal. While you need skills for playing, you also need these valuable resources to dominate and own the game.