Swarm attack

[Marc89]

I'm adding a Snake Swarm (Bestiary p. 249) to my encounter and I'm confused about how to handle its attacks.

If I'm right, the swarm occupies a 10x10 ft area ("space 10 ft") and his swarm melee attack enables it an automatic hit if it ends its turn on a square occupied by a PC. Thus, if two PCs are standing next to each other and the Swarm moves under both of them (provoking an attack of opportunity from both of them), will it hurt both PCs or does it have to choose which one to hurt?

Common sense tells me that a group of 300 snakes can easily damage both of them, but I'm not sure if I'm right according to the rules as well.

[Rathendar]

Everything in the area it occupies, so both PC's.

[joe kirner]

Auto damages all pcs in the 4 squares it occupies. Yes, all pcs get an aoo on it as it enters their squares. All pcs make a fort save vs distraction. If fail, they are nauseated.
I imagine you have read up on the swarm traits already.

[Marc89]

Thank you for the clarification!
Yes, I've already read the passage about swarm traits, I'm familiar with the rest of its abilities, this was the only question that gave me a hard time. Until now :)

[claudekennilol]

I was fighting a rat swarm in PFS the other day and the GM didn't have the swarm make any attacks of opportunity for us leaving its sqaure, was that right?

[Brf]

Swarms do not threaten and cannot make Attacks of Opportunity.

[claudekennilol]

Brf wrote:

Swarms do not threaten and cannot make Attacks of Opportunity.

Thanks, I see the relevant text now.