During my first game of The Old World, my Cold One Knights failed their stupidity test. My opponent and I were not entirely clear on how to interpret the rules.
According to the rules, the unit must move during the Compulsery Moves subphase in a straight line, but it does not specify a few details:
1. Is a unit that failed a stupidity test still allowed to declare charges and make a charge move?
Charges are declared and moved prior to the compulsory moves, and could therefor be seen as permitted. There is no explicit statement that denies this. But it seems both interpretations could be within the spirit of the game.
In previous editions of Warhammer Fantasy Battles, the charge would not be possible, but the move would happen prior to any charges. As this part of the rules was shaken up, a new interpretation is needed.
It says so in the rules... whoops
2. How far must a unit move when it fails a stupidity test?
The rules do not specify the distance a unit must move during the compulsory move. By contrast, this is clear for other compulsory moves such as fleeing. Is the controlling player allowed to choose how far the unit moves in a straight line? Is it permitted to not move the unit at all?