Why Your Rogue Should Have Improved Initiative - D&D 3.5

I have played a rogue Halfling for years.  Her primary weapon is a crossbow which she uses to make ranged sneak attacks.  She also has great dexterity and improved initiative which causes her to be one of the first to act in each battle.  But only recently did I learn that I have overlooked one of her best attack opportunities. 

I was not aware of the rule that an attacker in the first round of combat can treat her opponent as flat footed if the opponent has not yet acted.  This trivial sounding advantage is a huge boon to characters with the sneak attack ability and ranged attacks and a great initiative.

To clarify, if my rogue, Gwynne, has an initiative of 25, and the monster has an initiative of 18, and another rogue in our party, Berigand, has an initiative of 16, then Gwynne, acting first, could fire her crossbow at the monster and if she hits she could apply her sneak attack damage if she was within range for a sneak attack.  She does not need to be flanking or invisible because the monster is flat-footed (in the first round only).  When the monster acts, it could attack Gwynne who is not flat-footed (because she has acted already), or it could attack Berigand who is flat-footed because he has not yet acted in the round.  Unless the monster has a sneak attack ability it probably doesn't have an advantage in attacking one rogue over the other.

So my recommendation for crossbow wielding rogues is that they take "Improved Initiative", and "Crossbow Sniper" which allows sneak attacks from up to 60' away (instead of the default range of 30').  But most important, don't forget that your opponent is flat-footed in the first round of combat if you have a higher initiative and are acting before they do!

This is explained in the Player's Handbook on page 133 under "How Combat Works".  Also on page 135 under "Initiative", and on page 137 under "Flat-Footed".