Question about GE strength & special sites

[solmyr]

If a global enchantment is casted in a province with special gem discount magical sites, say e.g. blood 40 site, then how is the strength of the GE in terms of counter dispelling?

e.g. A blood GE require 100 slaves is casted in a blood 40 province and only 60 slaves are used due to the bonus of magical site. When someone else tries to dispel the GE, how will the dispel mechanism apply in this situation?

[JimMorrison]

If you cast it with the minimum required at that site, it will still just cost 30 Pearls to Dispel.

There was a bug for a long time, that extra gems didn't count until they surpassed the base cast of the spell. So your 100 slave ritual can cast at 60 slaves, if you cast with 80, it can still be brought down with a base Dispel. Only once you had cast with 101+ would it take more Pearls to dispel.

I thought the bug was supposed to be fixed, but I am short on time atm and can't dig through patch notes.

[Gregstrom]

Edit: Ninja'd by JimMorrison!

But... Dispel has to make an opposed roll against its target, so 30 gems is not a guaranteed success against a global cast with no extra gems. 40 would be pretty likely to succeed.

And don't forget that if the caster of either spell has more magic levels than the basic casting requirement, their spell will be more effective.