Combat Advantage / Backstabbing / Sneak Attacks

[DinbinFanfoom]

OK, Atty, I've read some of the PHB and I THINK this is how CA/BS/SA work, please correct me if I'm wrong.

Combat Advantage: gives you a +2 to hit because your target is preoccuppied (for example, you flank it, it's climbing, dazed, blinded, unaware of you)

Sneak Attack (rogue): you need combat advantage to use it, and a light blade, crossbow or sling, you can get a damage bonus (quite significant)

Backstab (rogue feat): Your sneak attack D6's become D8's.

Scenario: Our party is in a 25' x 25' room. 2 goblins enter from a doorway.

Q: How does Combat Advantage work in this case? IIRC, a rogue has combat advantage on anything that hasn't moved yet in an ENCOUNTER. Is that right? So if those goblins entered an encounter vs started a new one, this would differ, right? Assuming a new encounter (and the rogue had CA and the BS feat) he/she could sneak-attack with a thrown weapon (like a shuriken) and roll 1D6+bonuses against the goblin AC and then choose to add +2d8 extra damage? Is this how that'd work? Or if the goblins ENTER (get added to the encounter) does the rogue still have CA because they haven't yet ACTED in the encounter?

Kinda fuzzy to me. Can you 'splain? (Or Kiir)

[attriel]

New Encounter: If it hasn't gone yet, you can use the sneak bonus. I don't know if you have combat advantage specifically, but you get the attack.

New Enemy in encounter: Entering the combat would generally be an effect of the party now sees them or they have come through a doorway or such, and thus I would generally say that they are now part of the encounter, and their initiative started the round before , but I'll check the actual rules to see if I'm misinterpreting that

Existing Enemy: You get CA if a power is used that says that it grants CA to you. A number of them state that you get CA against the creature until the end of your next turn. Someone else's might say that a successful attack grants CA to someone of your choosing, until the end of their next turn or your next turn, or even the creatures next turn.

You also get CA, IIRC, if you are flanking the creature. To flank, you and the person flanking with you must be able to draw a line from any corner of the square you occupy to any corner of the square they occupy that crosses two opposing sides of the square the creature occupies (so, you actually have to be on opposite sides). I can't recall if you both get CA, or only the person the creature is NOT facing. In 3e it was both of you, i think in 4e it's only the person behind it, because the guy in front is fairly well attention-paid-to. Again, IIRC.

I'll try to look it up tonight

[Shiz]

And then there is marking...

When a target is marked, that target suffers a -2 attack penalty when attacking anyone other then the character who marked it.

[DinbinFanfoom]

And then there is marking...
When a target is marked, that target suffers a -2 attack penalty when attacking anyone other then the character who marked it.
Yeah, looks like a way of creating "warrior taunt"! 4e looks a lot like a paper-ized mmo!