notes for the potential DM...

area effects can and will ruin the day of a hiding character...if a PC decides to drop an aoe spell the circumstances can get quite interesting.

Do note that in small places like a house, players might have a very good idea where someone might be hiding and decide to start 'looking' the hard way.

Farie fire and light are not your friends...if PC's wise up...you could have a problem...same with detect evil or even detect magic (they have magic items...they blip even when hiding...since they will be hiding in plain sight most of the time, that means that they will not have cover from such magical sight.

Readied actions...someone is gonna ready an action to ruin your day..keep that in mind. A simple flask of oil will likely cause them no end of trouble since it will light them up for at least a round or two and every adventurer has at least one.

Do note their will saves...they are abominable...and no chance of a freedom of movement between the 3. Expect a savy party to charm, or even hold person or deep sleep...hell, any save or lose spell...most require a will or fort save...these guys have crap. Don't expect them to take too many hits. Depending on the party, and what they might be expecting, be sure to know that they probably will attack the first guy FAST...he should have some sort of means of getting away...I would suggest an illusion of him or another 'faceless nobody' to converse with the party while he hides and maintains concentration. Otherwise they will likely just kill him and question his corpse...

A point of note...if they have access to such magic as well, why bother talking to them...strike hard and fast, leave no warning, talk to their spirits when they are dead. As such, have the shadow cause a noise out back, and the other guy use an illusion to cause a noise out front...when they separate, the shadowdancer locks the front door while the assassin studies one of the others insideor going out back...they should have a bit of time. A scroll of summon monster III or IV might be good as a distraction. Attack PC's one at a time, sneak attacks, death atacks and poison...shade blindsides one while they deal with the summoned monsters and backs off into shadows...by the time they get back together, at least 1 or two of the party will be weakened and another 1 or 2 dropped due to paralytic poison or just plain killed...spellcasters and clerics first of course...the fighters they can handle. Against wizards and clerics, they might just be screwed unless they get the drop on them specifically. Just try not to go too far overkill...you want the PC's to have a chance...Might be neat if one of the enemies captures a party member and their partner is also captured by the party...exchanges are always fun.