If you try to tumble past a horde of orcs such that every 5 ft step would cause an AoO, do you make the rogue go through his entire move (and take ALL the AoOs)? Or does he stop when the first AoO is done against him?
I'm thinking that since the rogue gets to do the whole move even if he fails, that he has to take the whole move even if he fails. It's always annoyed me that there is simply NO way to stop someone from getting past you; at best you get to take a swing at them.
First of all, a rogue can only tumble 20' in any given move. That's not really enough distance to tumble past a whole horde of orcs unless he's tumbling in a straight line, through four spaces all occupied by orcs, with orcs on either side. Most of the time, he'll be tumbling past two or three foes at once, tops.
Now if a rogue wanted to try and stop between foes (say if he was low on hit points and wanted to "abort mission" if the first orc managed to whack him good,) I'd let him, but I'd force him to make a separate tumble check for each "leg" of his journey. Basically, he'd designate his first move (past foe #1,) and roll a tumble check. If it succeeded, he could designate his next move and roll a new check for the next orc. This is in-line with a Sage ruling that you can break up the 20' tumble distance, but must roll separately for each stretch of tumbling.
As for stopping someone from passing you, what you want is the Psionic Feat Stand Still
. It gives you an AoO when someone tries to enter your threatened area, and if you hit them for damage, it prevents them from moving forward at all. This still wouldn't prevent a rogue with a successful tumble check from moving past you, but it would
prevent a rogue from moving past you on a failed check.