There is currently an error with the Ability Enhancements Challenge, in which the base stats of the PvE characters were set to lower values than they should be. This will soon be corrected and the values reverted back to their intended numbers.
As this bug reduces the difficulty significantly below the intended levels, in the near future we will be “rolling back” players that were able to unintentionally bypass the difficulty of the higher tiers. The players being “rolled back” are those that got 1-3 Stars on Tier 11 and Tier 12 after the date of April 14th, when the bug was encountered. Note that we will not remove the rewards those players earned in that timeframe - you get to keep them.
To ensure that this doesn’t create an imbalance for lower-level players, we’ll be sending all players that did not advance to these Tiers a number of Ability Materials available at those higher levels.
Thank you to those that reported this issue, so we could promptly investigate.