Halo: Reach has brought a whole new way of unlocking you ranks in competitive multiplayer. Ranks are now unlocked by earning credits (cR). By completing various daily and weekly challenges you will earn credits. By completing games and earning medals you will also earn credits, as well as slot machine pull which will net you a bonus every round you play. This is a level by level guide showing how many credits you need to earn for each new rank in Halo: Reach.