Maybe we should start with the highest-level dungeons?
Give me the save file! I can easily handle the highest-level dungeons. I think I accidentally twitched my finger or something during a game with Rimpel, and I randomly pressed a button while looking at the spellbook, and I cast Death Wave on all my units in the highest-level dungeon, which is comparable to 7 Magic Arrows aimed at my own troops. That's why I lost my troops at the beginning of the game. So, please don't remind me about the highest-level dungeons.
Marazhan also mentioned that he lost a game because of a single accidental button press.