Would this destroy the ability to use the Beam for the rest of the game, or would it destroy the whole solar engine, also removing the +1 int?
The solar engine is not a magic item, so the spell is an inate bound spell, like warrior priests prayers. If you miscast those, the model can not cast futher bound spells that turn, that is all that happens. Demelain
Awesome, thanks for the explanation. This could be especially awesome in smaller games where you have only a lvl 2 (or no caster at all), and you can just chuck a lot of dice there.
Yup. I regularly do this with my Warrior Priests. If I really need that spell off (generally 5+ ward), I chuck 6 dice at it and hope for IF. No chance of blowing up from Misfire, but it can't be countered if IF is rolled.