Once you reach level 40+ the game becomes pay-or-grind-for-months... seriously, all the weapons in the Shop geared for Level 40+ cost a lot of Rubies, the Contract Weapons cost too much gold to complete (again, really grind-y), and the Gauntlet Rewards are really horrible. Unless you cough up money you'll be stuck opening Epic Chest a lot, and I mean a LOT, just to get a decent weapon :P