Someone else posted about problems with attacking and loosing even though they were more powerful. Our group has been testing this out over the past day and it does appear that there is a big problem doing multiple attacks on the same player. Even with a 2x tactical advantage we have discovered on the second attack that the odds of loosing are much higher.
Now you could say that it could be because you lost a high value unit on the first go around. Problem is in several instances this happened even though the attacker did not loose any units during the first fight.
And this also seems to occur more often when doing the consecutive win challenge which sets you back to 0 every time. Not even going to bother posting this in Technical because this may be an intentional change.