Great Zero dungeon training If you buy 3 clocks from the shop in your 'home town', you'll be able to enter the Kritias dungeon for 3 (max) times. Each run gave my Zero like 70% because the monsters give like 200k per mob there. You should definetely try that out with the 2x exp coupon you get daily! The clocks cost 5 time coins each, so 15 coins a day for really good exp.