So how does Sneak Attack work? (IWD2)
 

As I've been playing some IWD2 I've noticed sneak attack only seems to work once or once per a few rounds. I'd like to see some other experiences with sneak attack in order to confirm my suspicions.

So far I've tested this: take a party member, strip of AC, and let the rogue attack her from behind. First attack always seems to be a sneak attack. But after that it takes something like 4 rounds to get another. Two-weapon fighting does nothing to change this, it only adds more normal damage attacks.

I've not tried the use of either invisibility or immobilization, but I'd imagine the results aren't that different. Any input from the experts?

Re: So how does Sneak Attack work? (IWD2)
 

Sneak attack damage is applied any time your rogue makes a first attack from a flank or rear position. Once sneak-attacked, enemies tend to attack the rogue that sneak-attacked them, after which (as makes sense) the rogue cannot sneak attack that enemy any more, unless that enemy switches its attention somewhere else.

To get more out of your sneak attack, you can switch targets often, in theory sneak attacking a different enemy every round. While that may increase the amount of raw damage your rogue inflicts, it may need more micro management (e.g. by setting your autopause feature to pause after the end of every round so that your rogue can switch targets without wasting any time), and may also be less efficient in the sense that it is often better to kill a wounded enemy quick.

Re: So how does Sneak Attack work? (IWD2)
 

Of course that ignores the fact that even if the enemy didn't turn towards your rogue, he only would apply sneak attack every four rounds as I've found out. Try switching between two target (like two of your party members) and you'll notice if you switch back to first before 4 rounds he'll not do any sneak damage.

Which has made the rogue mostly useless in IWD2 because he needs the sneak attack like in pnp.