The Drow: Tips for the DM
From Lords of Darkness
Drow are some of the most talented and magic-proficient creatures in all Faerûn. Their sleep arrows carry potent any poison and in sufficient numbers can bring down almost any group. They focus on spellcasters first, leaving other characters for a second volley or finishing them up in melee.
The Stealthy feat means that even an average drow fighter (Dex 12) in a chain shirt (armor check penalty -2) still has a +1 bonus on Hide and Move Silently checks. Given that a typical NPC drow rogue has a Dexterity higher than 12 (using the standard array and the +2 racial bonus), a group of drow fighters can prepare a reasonably stealthy ambush. When used by a rogue or wizard, the benefit of Stealthy is even greater.
A drow fighter or rogue with Twin Sword Style makes a formidable opponent despite his lighter-than-normal armor, gaining a good AC bonus and the extra attack from the second weapon.
The Daylight Adaptation feat interferes with the plans of adventuring group that expects all drow to react to the sun as if they were vampires. The heroes might let their guard down during the day, expecting drow activity only at night. Surprise them with an attack during the middle of the day.
Because a hand crossbow and twenty masterwork bolts is bonus equipment for drow with the proper preferred class, a group of drow rogues within a city can strike from almost anywhere, sending a rain of tiny poisoned bolts upon the heroes, then disappearing, without any bulky items to draw attention to them (assuming they have disguised themselves as non-drow, of course).
Above all, remember that while the drow of the Underdark are constantly fighting each other, the drow of the surface rarely do. They are not stupid opponents, and are capable of devious and long-reaching plans that can take many game sessions to unravel.