I will be being as vague as possible so as to not cause spoilers or force sides.
We are playing a game using primarily pathfinder rules with a bunch of potential homebrew rules, but are looking for pathfinder guidelines on this bit. There is a huge creature that is full attacking a groups of pcs. It has multiple tentacles with grab and constrict. On one turn it hits, grabs and constricts all four players, ending its turn with all four grappled.
One of the players believes there is a rule stating it cannot do that without a -20 penalty to remain ungrappled itself to continue grappling and that it should need to hit, grab,constrict then drop to continue doing it to the next creature. As the rules for grappling are quite vague and rather spread out, we were hoping that you, the forum dwellers, could help us out with the rule set here. There are NO house rules currently modifying this creature. What if any penalties or limitations should be/have been in effect in that round, and if possible, can you cite the rule as well as your understanding. I have a funeral to go to as well as a wake before we meet again, and do not have the time to pour over my books, nethys and the pfsrd for guidance, and am hoping you can assist us.
It can totally grapple without the -20 penalty, it just is going to take the penalties for being grappled. Nothing in the grappled condition will prevent the NPC from continuing to make their allowed attacks including grapple checks they will simply suffer some penalties in doing so.
The reason why the NPC will want to hit, grab, constrict, and drop is because on it's next turn the NPC will not have the ability to maintain multiple grapples. There are some feats that will allow you to grapple more than 1 person, but it's not a something that an enemy should casually have. Now that said, a monster with tentacles, grab, and such should probably have special rules written allowing it to maintain grapples against multiple enemies, but they don't.
And the most effective way to run an enemy like this is to do the hit, grab, constrict, drop routine against 1 character, inflicting maximum damage through multiple constricts. In fact, maintaining a grapple leads to less damage because you can only constrict once.
What normally prevents people from grappling multiple creatures is action economy and penalties adding up that make it untenable to succeed. Because but you're player isn't correct that having the grappled condition would somehow prevent you from continue to make additional attacks and grapple checks.
Just do what I do and interpret the "Greater Grapple just maintain in any way once in the round" clarification to mean that you can full attack, grab, skip to next turn, full attack again and if you hit with the same attack that actually grabbed with from last round, make a maintain check as you would for a normal maintain. You can now have your grapple monsters act like actual grapple monsters instead of more-dangerous-than-normal-tickle monsters.
I suppose, but I'm not sure that is how the rules should be interpreted. Plus most monsters don't (by default) have the greater grapple feat.
I would probably use the Kraken as a base or an inspiration for this creature, and give the creature Tenacious Grapple (Ex) if you haven't already. And then use this: Grapple Flowchart <---- The grapple rules are highly confusing and this flowchart has served me well.
If you don't have the Tenacious Grapple ability, then after your 1st grapple, you are also considered grappled, so all your subsequent grapple attempts to grapple multiple PC's/creatures will be made at the -20 penalty. So you can get around all that nonsense by taking the Tenacious Grapple ability, and grapple multiple foes without also being considered grappled after the first target you grapple.
You said you're using a monster that has no homebrew stuff so I assume it's from the bestiary, can you link it so we can give more accurate advice?
I suppose, but I'm not sure that is how the rules should be interpreted. Plus most monsters don't (by default) have the greater grapple feat.
The greater grapple clarification isn't specific to greater grapple, as developers pointed out, but just a normal feature of the grapple rules when combined with the fact that *most* creatures will never be able to make more than one grapple a round, be it initiating or maintaining. Even by a strictly RAW interpretation, nothing would stop a grapple monster from progressing a grapple with a different grab attack (say one of the Kraken's 7 other tentacles), as grapple isn't normally tacking what limbs you are using except for what modifiers you have (e.g. a humanoid not using 2 hands), but juggling and even potentially insta-pinning as a grapple monster is more clearly an overstep than hitting round over round consistently with a single attack to earn grab-grapple checks that would then maintain.