It makes it virtually impossible to estimate what each move will result in, and makes you play with movement so cautiously that it slows down the entire game. You try to hide every mm of each mini, because you never know if that basic troop unit isn’t going to completely wreck one of your troops out of the blue with a combo.
It also makes some matchups super spiky, as in « you fail 3 dice throws and you’ve lost the game », which is also very annoying.