Magic circle stacking with Shield of Faith

[Roticet]

Does magic circle against good/evil stack with Shield of Faith?
Both provide deflection bonuses to AC, which to me, says that they don't... But if one casts both, they choose which bonus to gain, and still gain the +2 save bonus.

Do I have that correct?

[Khedrac]

Pretty much correct.

The recipient gains both bonuses, but only applies the larger one to their armor class (so if one expries or is dispelled the other is still there).
They not only still gain the saving throw bonus from protection v alignment, but they also gain the supression of mental control and the prevention of contact from summoned outsiders (unless they attack them).

[KillianHawkeye]

Just to note: you don't choose which bonus to take. You automatically take the higher one.

Bonuses of the same type overlap, which means you get the best one while the others do nothing until such time as they become the best of that type.

[Roticet]

Thanks guys, I thought I had it correct, but the wording is not your best friend on no sleep with an encounter heavy session coming up later today as of this posting. Also thanks for clarifying that I'm forced to take the higher bonus. Doesnt matter for now since both spells will be providing a +2 deflection bonus strictly.

Unless I have that wrong... a lvl 5 cleric troglodyte would still only provide a +2 bonus from the shield of faith correct, not three? My understanding is that the spell is linked to the class lvl and not overall lvl. Again sleep deprived, so thanks for the help.

[Chronos]

Just to note: you don't choose which bonus to take. You automatically take the higher one.
A case where that's relevant: You're wearing a Ring of Protection +1 (which gives a +1 deflection bonus against everything), and also have a Protection from Evil spell on you (+2 deflection bonus, but only against evil creatures). You're attacked by a creature whose alignment you don't know. If you had to choose which bonus to use, you'd need to guess. But you don't need to: If the creature is evil, you'll automatically get the +2, and if it's not, you'll automatically get the +1.

EDIT:

Unless I have that wrong... a lvl 5 cleric troglodyte would still only provide a +2 bonus from the shield of faith correct, not three? My understanding is that the spell is linked to the class lvl and not overall lvl.
It depends on caster level, which is usually the same thing as class level in the appropriate class, but some things can change that. Just having racial hit dice or a level adjustment won't, though.

[Roticet]

A case where that's relevant: You're wearing a Ring of Protection +1 (which gives a +1 deflection bonus against everything), and also have a Protection from Evil spell on you (+2 deflection bonus, but only against evil creatures). You're attacked by a creature whose alignment you don't know. If you had to choose which bonus to use, you'd need to guess. But you don't need to: If the creature is evil, you'll automatically get the +2, and if it's not, you'll automatically get the +1.

EDIT:

It depends on caster level, which is usually the same thing as class level in the appropriate class, but some things can change that. Just having racial hit dice or a level adjustment won't, though.

Good to know. I'm dm for this campaign, so thankfully I know the alignments. And thanks for the clarification on class lvl vs racial hit die. That does clear things up.