@_@ What the hell are you babbling about the CPU cheating? I said that it can be exploited by HUMAN players and since you can challenge other players online, that makes it an issue.
In case you guys still don't get it; Nightmare must be hit by his own Boulders and then some black gems appear around him which you must pick up in order to deplete his energy.
One more thing: In order to get the "Kill Transit Trader" favour, talk to the first trader with your loaded gun, then put the gun down and talk to him again. This must be done BEFORE the cigar trade.
The Tag Team Triumph Badge shouldn't be Hard, it's way too easy to get. Cave 5 on the other hand requires the correct setup and maxed out troops and magic.
Really inconsistent difficulty level. 2 Shamans plus Totem are ridiculously hard, the Poison Golems in the same town are piss easy. And it takes too long to build up skills and buy equipment. Good game overall though.