Ok, I knew there's been a few posts about this, what if you grappled someone from there mount, or trip the mount, and they fall. the mounted person takes fall damage but what's next?
What brought this in was the CR 10 fight for RAPPAN from taking the bandits out of the Mouth of Doom. We only won the fight by meeting one of the conditions. BUT we as the party where lvl 4 at the time with 6 of us. still higher then a epic level fight, bearly made it.
But anyways there's no ruling for that if the mount was tripped they aren't. We did a house rule that they would have to roll a ride check so that they wouldn't be prone, if they made the check.
Since I actually live on a ranch, I told the DM this, F%#~ you if you let the rider not be prone unless he makes the skill check, but if he doesn't well that's just f$#$ed up, no one should beable to not be prone when they fall from a mount. that's just Over powered imo.
And another note I think my DM cheated with the fighter with a keen greataxe, he got tripped and was able to use a potion of enlarge person after he moved and attacked.
Side note: I think the DM wants the party to be TPKed that fight in all honesty. and he actually kinda complained about not actually attacking a downed/stable PC. I honsetly think he just wants us to s$*+ out characters at this point, i don't mind that, but the encounters he's been giving us, he's done this 3 times already, put us against a CR WAY higher then a fight we should actually do. I think he's doing this on purpose. and I don't want my Death cleric to become a pawn of the big baddy too.