How does Magic Circle Against Evil work?

[Nareau]

What would happen in the following situation?
Neutral Cleric Joe and Rogue Sue go delving in their local dungeon. They realize they're going to be fighting some evil cultists soon, so Joe goes ahead and casts Magic Circle Against Evil on Sue.
Moments later, Sue goes toe-to-toe against an evil orc fighter. Joe quickly casts Summon Monster to help Sue out in the fight (he summons a Fiendish Leopard, a CE creature). Sue positions herself in such a way as to flank the orc (with the Fiendish Leopard on the other side).

Can the Leopard attack the orc? More specifically, is the orc affected by the Magic Circle Against Evil? If he is, the leopard won't be able to even touch him.
If the orc is affected by the MCAE, and the Leopard can't touch him, is he still threatened by it? You see where I'm going: Is he still flanked by it?

I'm thinking that, by the rules, the MCAE does affect the orc (meaning the Leopard can't touch him). However, the Leopard still flanks him (because the leopard threatenes the space the orc is in). Common sense tells me that God is smart enough not to bestow the benefits of MCAE on your enemies. And even if God doesn't make that distiction, you can't be flanked by someone who is incapable of harming you.

What are your thoughts?

 

[rushlight]

The way I read it, all the evil creatures are affected by the circle. The difference is that the orc could still attack the rouge, but the rouge would get the bonues from the circle (+2 to AC). The leopard wouldn't even be able to get in range to attack the orc, as it's a summoned creature and couldn't come within 10 feet of the rouge. So unless the rouge stayed more than 10 feet away from the orc (and thus the orc would be outside the circle), the leopard would just get to watch...

In the end, the leopard couldn't threaten the orc unless both creatures were outside the circle.

 

[Nareau]

Interesting...

That's not how we've been playing it at all. If I understand you correctly, it sounds like you're suggesting that the MCAE creates a spherical barrier with a radius of 10' (centered on the target of the spell). This barrier is the same as described in Protection From Evil, right? This sounds like a reasonable way of doing it, we just never thought of it that way.

Do other people play this way? Or do you just assume that the spell affects everyone in its radius as though they had Protection from Evil cast on them?

 

[rushlight]

Well, to quote the beginning of the spell desription on Magic Circle against Evil: "As 'Protection from Evil', except that it encompasses a much larger area and its duration is longer."

Protection from Evil states that the 'barrier' extents 1 foot around the user. Seems to me thats the way it was intended to work.

 

[Ziggy]

I'm pretty sure that the ruling outlined by rushlight is correct.
Rember that the magic circle alse can be used to trap a creature inside the circle, strengthening the theory that circles act as barriers.

.Ziggy

 

[Nareau]

OK, so now I have new questions


The description of PfE states:

This spell wards a creature from attacks by evil creatures, from mental control, and from summoned or conjured creatures. It creates a magical barrier around the subject at a distance of 1 foot. The barrier moves with the subject and has three major effects.

So if it's the barrier that does these things, what happens when someone manages to pass through the barrier?
For example, can a vampire run up to Sue, stand right next to her, and Dominate her? He's not trying to do it through the barrier, and it's the barrier that "blocks any attempt to possess the warded creature".
If an Evil NPC summons a creature to appear right next to Sue, can it still attack her?
Really, if an enemy crosses the barrier, do the people inside retain any of its benefits against that attacker?

 

[HeavyG]

Here are my questions :

1) What happens when you try to summon an evil creature inside a magic circle against evil ?

2) With Protection from evil, if you attack a creature or try to push it away, the protection vs summoned outsiders fades away. With Magic Circle, what happens if one of the protected creatures attacks a summoned outsider ? Does the whole Circle stop warding outsiders or is it just that attacker who loses the protection of the circle ?

3) If someone steps out of the Circle, attacks, then enters the Circle, is he then protected from the creature he just attacked ?

4) Do outsiders sense the protection or will they lose time trying to attack a warded being just to realize it doesn't work ?