So the effect its just on one dice result!? Well I don't see the hidden force, can you explain me please? If i use FoC on a unit os Saurus Warriors for exemple, i can modify just one dice attack of all attack they made....thats correct?
Yes. I'll try to explain its usefulness. First of all' remember that the +1 will affect a dice after you see the roll, so when you use it, it will always turn a failed roll into a success. Cast CoF on a stegadon. Hero phase: use the +1 to modify the teleport or to increase the extra move granted by skink Alpha. Shooting: it's always nice to hit with the giant bow. Charge: +1 to charge can make the difference Combat: a success with an attacks or a save. And this will work also in the opponent turn: Shooting: turn a failed save into a success Combat: same as above. Basically, you have a potential of 6 failed rolls, turned into a win. Even if you use it only half of the time, a spell that grants 3 positive results in a round is no joke. Now imagine it on a EotG, when you roll for the effects of the engine (plus all the bonuses you may need in the other phases). Or on a Knights unit, when you can turn a 5 into a 6 for mortal wounds. Or on a Carnosaur (Yes, it will affect also the contest by the bloodroar)
To be honest, it does feel lackluster on account of it only affecting 1 roll. Outside of special attacks or abilities like the EOTG or an attack like a stegadon's crosbow that can easily be a bit underwhelming. It's a bit of a weird spell. On the one hand getting a +1 to anything is absolutly briljant, on the other hand getting a +1 to a single dice when you're rolling say 20 of em isn't all that relevant. So it's a bit odd..