The problem with credits is they are not giving enough options to build credits quickly. The high cost to MTM cards, especially the R6 and R7 cards, cost more credits than one can quickly replenish. They (Mobage) need to offer more ways to acquire credits. I had 150+ million credits beginning of summer. I as of this writing have 14 Million credits left. I have no more resources to get credits other than missile defense, point rewards and daily rewards. the game has a SERIOUSE balance issue. I am sure most new players are seeing this first hand.