Now that the event's up and the rate is out, let's do some fun math to find out the chances of getting a Z! I'm doing this under the generous assumption that the game does 2 guaranteed gold+ pulls and 8 normal pulls. Let's call the former the GPull and the latter NPull. For the GPull, I'm also assuming the chances are prorated. So the chances for Z, SS, and S are respectively 8/33, 10/33, and 15/33. The chance for both pulls to be gold is therefore (25/33) × (25/33) = 625/1089 = 57.4% Now, for the NPull, the chance for a Z is 8%. The chance for getting no Z in all 8 pulls is therefore (92%)^8 = 51.3%. For the entire 10 pull to have no Z, it must have both no Z from GPull and no Z from NPull, which is 57.4% × 51.3% = ~30%. Therefore, the chance of getting at least one Z is 100-30 = 70% I also would like to remind everyone again that this calculation is made with the assumption that the game reserves two pulls before the 10 pulls are made. If the game does another method, like doing 10 pulls first and just altering the last results based on the results, then the chances are even lower.