|Well son of a bitch...|
Suddenly Here's Why Charisma is Important
Here's how it works. If you have this feat (you don't have to be a weretiger or a Fanglord to possess it, but you should be able to explain how you did learn it if you aren't one of these creatures) you make a bluff check as part of every initiative check. Every enemy makes a sense motive check. Every enemy who fails a sense motive check doesn't regard you as part of this fight, and typically that means they'll ignore you. If all of the enemies discount you, then you may act as part of the surprise round.
|They never saw it coming.|
That sounds great, particularly given that sense motive isn't something most of your villains are going to have a lot of points invested in. So if you take a little time to buff your bluff by taking feats like Skill Focus or Deceitful, you're going to wind up participating in the surprise round a lot more often. With that said, a single move or standard action is only going to let you do so much in combat. This is particularly true if you are a melee combatant instead of a spellcaster.
Unless, that is, you have the 4th level ability of the rogue's Bandit archetype; Ambush.
Ambush says that whenever you act in the surprise round you may take a standard, a move, and a swift action as if it were a regular turn. Not only that, but if you're mixing and matching your rogue archetypes you can combine Thug with Bandit, making a combination that dovetails nicely.
It's Amazing What You Can Do With One Turn
How many times have you been looking at your enemies as they spring up for a surprise round and known you could end this as soon as it began if you could only act? Casting entangle on a bunch of bandits hiding in the brush, throwing an alchemist fire into the midst of a swarm before it can engulf the wizard, or putting an arrow into a spellcaster to disrupt the fireball that's about to be dropped on your head is something that will really change the course a fight could take.
Or, if you're just getting a full round all to yourself, why not get in as much sneak attack as you can with it?
Also, if you're going to be going in the surprise round then you may as well go before all the bad guys, too. Here's How To Top The Initiative Order (Almost) Every Time to help you be the fastest off the mark.
It's been brought to my attention that the feat has been altered since the publication of Blood of the Moon. The errata, buried in a forum post but linked here at the D20PFSRD renders the above guide moot. However, DMs who prefer to use the original version of the feat in their games may still find this interpretation to be of use.
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