Pathfinder: A rule when they're outnumbered!

[kottakinge]

Hello there fellow DM!
I would like to have a precision on the grappling rule.
Some creatures (ie zombis) attack en masse, trying to grab the character and put her on the ground.
Let's said that 8 zombis can circle a PC, only 1 make a CMB with a +2 bonus for each zombis that help (so +14 bonus), so all of them are considered grappling with the PC?
If they managed to get a hold then will they all make a natural attack against the PC?
Thanks!

[Mortavius]

As I understand the rules, only the zombie that makes (and succeeds on) the Grapple check is actually grappling with the PC.

The other zombies may be able to make attacks on the grappled PC; I'm not sure what the rules are on that, but it'll be in the book. I think the main answer to your question is that only the one zombie would be considered to be involved in the grapple; the rest are just assisting that one zombie.

[Ryan Naylor]

Mortavius is right.

One zombie is grappling; the rest are aiding another. They are free to keep aiding another, or they can make attacks against the PC (who now has the grappled condition). Or they can just wander off. They don't do automatic damage; they have to roll normally.

They can all try to grapple independantly, however, so they don't get the aid another bonus, but if the PC slips out of one, the others have still got a hold, and they can all do automatic damage.

This is what happens in the movies when you slip in front of a zombie horde.

[Gonzoron of the FoS]

Yeah, 3.5 had rules for multiple creatures grappling, but PF seems to have removed them and replaced them with an application of the Aid Another rules. It's not clear to me what happens in PF if you attempt to grapple someone who is already grappling.

By strict interpretation of the rules, I think Ryan's right, they could each establish their own independent grapple with the target, but not be grappling with each other. (The requirements for taking the grapple action don't say that the target can't already be grappled. But the "Multiple Creatures" section doesn't mention that possibility and talks about "The creature that first initiates the grapple" being the only one to actually grapple. It's not clear if Aid Another its option or an override of the standard grapple rules any time multiple creatures are involved.)

If you can grapple someone who's grappled, I'm not sure what happens in the case where one grapple-initiator moves the grapple-target away from another grapple initiator. Does it pull the other grappler with him? (It could be as the result of a grapple check to Move, or in this case: multiple creatures with reach grapple a medium creature. (Say a pack of trolls fighting over a tasty human) When you initiate a grapple with someone not adjacent to you (using reach) you can move the grappled creature adjacent to you. What if one troll grapples the human and puts him in front of him, then another grapples the same human and puts the human behind him? Does the first troll move? If not, is his grapple broken?)

[kottakinge]

I see a grappling horde much like a swarm.
Only one grapple check (the 1st one) aided by the others creatures.
And all creatures automatically attack and deals damage.
Seems lethal but if the PC beat one grapple check she's free.
These has the advantage to frighten PCs when confronting a horde (yes i like the walking deads) but do not make mass grapple an overpowered weapon considering the fact that only one good check and you're free.

[Garudos Celestar]

I see a grappling horde much like a swarm.

...or a mob, from the 3.5 Dungeon Masters Guide II. I believe there were full statistics for a mob of zombies in Exemplars of Evil.