Let’s face it. You’re eventually going to have to group to get that item you’re craving. After level 40, there are very few items you can acquire alone that are really great. The rogue is one of the most diverse classes in the game. You need to know exactly what works best against what enemy and what you can do in a group to make things go by smoother.
Pure Melee Groups
This usually happens when you’re in a quick group to finish a quest. You don’t have a full-time healer or caster to help. Pure melee groups do not work in an instance. You have to decide based on your group mates, what tactic is best.
If you don’t have a paladin things are a little different, since they have mild healing abilities and are still considered melee. Basically, you have a great damage group but you need to take the least amount of damage possible. Have the warrior pull and open with Cheap Shot(CS) and use Kidney Shot(KS) once you get to 5 points. Only use KS once though, as it has diminishing returns and will not work twice on the same opponent. If you have another rogue in the

group, let them do all the damage while you concentrate on stunning. It’s better to each have a specific role then to just do whatever you feel like.
If you have a paladin, things change a tad. You can opt to have the paladin use their aggro reducing aura and go for full damage or have them use their attack-increasing aura and go all out for damage. The problem with the 2nd option is that you will be getting hit. There is no class that can stop a rogue from getting aggro when that aura is in effect. Since a paladin can heal, it’s best to take down the enemy as fast as possible and get healed after the fight.
If you’re with a hunter and no paladin, make sure their pet has the growl skill (growl is a hate generating skill, meaning the pet will be the tank). If they don’t, you’re going to get hit a lot so prepare for that. Opening with Ambush is a good idea here simply because the hunter can do a ton of damage with their ranged weapon and you want the target to die as fast as possible. I prefer to use Kidney Shot here because the damage from Eviscerate is easily offset with the hunter’s damage. Matter of fact, grouping solely with a hunter is a good thing if the pet can hold aggro for long enough. A hunter’s DPS(damage per second) is amazingly high and is second only to the rogue.
If you’re in a group with a fellow rogue, I highly suggest you both use CS but not at the same time. One of you opens with CS and starts attacking normally. When the first CS wears off, the second rogue opens with CS and then you both attack. You’re looking at near 10 seconds of no damage against you with some really high damage against the target.
Generally though, in a pure melee group you’re going to want to use stuns as much as possible. It’s great because the group can tear through creatures without too much trouble and the damage inflicted on the group is greatly reduced.
Pure Caster Groups
These groups are more common in the higher levels as AE (Area Effect) killing becomes more effective. Basically, pure caster groups are all about instant damage and do not have the hit points to take excessive damage. They are all ranged attackers. Regardless if you have a priest or not, it’s all about the offensive spells.

Make sure you have crippling poison on, this is very important as you don’t want the enemy running around. In this case, you want to open with CS and then KS once the target moves towards the casters. With Initiative, you’ll usually have a 3-4 second stun after opening which is more than enough time for the casters to kill the opponent. Try stunning in a group of casters and I near guarantee you will make their friend’s list after an enemy drop.
Since most caster groups are AE groups (Area Efffect spells), the want the targets to stick close together and not move around. Crippling Poison and stuns keep targets immobile and very slow, helping the group tremendously.
Balanced Groups
This is generally what you’re looking for in an instance. It consists of a healer (priest/shaman/paladin/druid), a tank (warrior/druid/paladin) and a DPS unit (rogue/hunter/mage/warlock) with 2 others. Sometimes you’ll be in a group with a priest, paladin and 3 rogues. This can be a great thing.
Ideally in a group, you will be the only rogue. You will also be the designated puller in most cases. If you’re not, I highly suggest you ask to become the puller and get some practice in. As a puller, follow the steps I described in section above.
If you don’t pull or you are a secondary rogue then you will have an interesting choice that depends on the group dynamic. Try one style for a few kills then swap to the other and decide which works best. I suggest starting with stuns, that is, opening with CS and letting a 5pt KS off for 10 seconds of stun total per kill. Very effective and gives priests the ability to do other things than heal all the time. This tactic is especially lethal against casters, more so when combine with Kick.
The second style is to Ambush and Backstab then finish with Eviscerate, so a pure damage rogue. You’ll want instant poisons on your daggers in this style as well. If you are fighting a caster, remember to use Kick. It has a very low energy cost and works just like a 6 second stun as casters do very little melee damage. If there are a lot of targets attacking your group and you know your Eviscerate will be waster on a target, opt instead for Slice and Dice. It will allow you to increase your DPS against the next target.

In higher level encounters, where targets have very high hit points and armor you might want to completely swap off to DoTs. If you find you are doing very small amounts of damage, try opening with Garrote and finishing with Rupture with Deadly Poison on both daggers. Not uncommon to see 400+dps.
If you are grouped with another rogue, ask them what poisons they are using and what fighting style they are going to use. More than one rogue using crippling poison is a waste, as is more than one rogue who’s using stuns. That is, unless you plan out your stuns and one of you always open with CS first while the other waits 5 seconds to open with another CS and you both ignore KS (which after 2 CS would be severely weak) allowing you to still have nearly 10 seconds of stun and 5 point Eviscerates each. Talk to the other Rogue so that your attacks don’t overwrite each other.
Good Group Buffs
If you’re in a group, might as well take advantage of the buffs other classes can give you. Here’s a listing per class of buffs you should try to have on as much as possible, in the order of use.
Priest
Fortitude – Various levels but the top one gives 79 Sta for 1 hour
Shadow Protection – Gives 70 Shadow Resist for 20 mins
Paladin
Blessing of Might - +220 Atk for 5mins
Salvation – Reduce Hate Generation by 30%
Blessing of Kings - +10% to all stats
Devotion Aura – Adds 861 AC
Fire Resistance Aura – Adds 30 Fire Resistance
Druid
Mark of the Wild - +340 AC, +14 all stats, +25 all resistances for 30m
Shaman
Note: Totems do not stack with main-hand poisons
Windfury Totem – 20% chance on attack of causing an additional attack with an extra 445 Atk

Flametongue Totem – Each hit with the main-hand causes 20-60 additional fire damage