Follows is the official WoW Rogue forum poison FAQ, since I got a greenlight to remake the original so that mine was the first post. Pertinent questions will be added to the FAQ section at the end.
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Version History
Version 1.2: Updated for TBC.
Version 1.1: A few new FAQ questions added.
Version 1.0: First version.
How do you train in the ability to create poisons?
You'll need to complete a quest first to gain the ability to create poisons. This quests requires you to be level 20 before you can receive it.
For the Alliance: http://wow.allakhazam.com/db/quest.html?wquest=2360
For the Horde: http://wow.allakhazam.com/db/quest.html?wquest=2460
Once you complete the fairly short string of quests you will be able to train in specific poisons from any Rogue trainer.
Where do you get the materials to make poisons?
Find a Shady Dealer, Poison Vendor, Poison Supplier or another similar-sounding name. They are usually around Rogue trainers but are also often found in other locations around town or in areas without Rogue trainers (i.e. outposts).
What effect does each poison have?
Instant Poison - Each strike with your weapon has a 20% chance to deal an additional amount of nature damage. My (and most Rogues) favorite for PvE encounters. May be learned at levels 20, 28, 36, 44, 52, 60 and 68.
Deadly Poison - Each strike with your weapon has a 30% chance to apply a twelve-second Nature-based Damage over Time ability to your opponent. This DoT will stack up to five times on your opponent. If the poison gets all five 'ticks' to do it's damage the damage dealt is about equal to Instant Poison, but Deadly Poison is 10% more likely to be applied. Deadly Poison may be trained at levels 30, 38, 46, 56, 60, 62 and 70. NOTE: Many Rogues don't like this poison for two reasons. a) Often, especially while soloing, the DoT component won't complete all of its ticks, thus causing you to lose damage when compared to Instant Poison, and b) It essentially prevents the use of all of your Disorient abilities (Gouge, Blind) because every three seconds the poison will deal damage and break those abilities. However, this poison has become vastly more popular in both PvE and PvP due to the advent of Mutilate (increased damage when the target is poisoned) and the raising of the debuff limit to 40 prevents the poison from being 'pushed off' by other effects in most situations.
Crippling Poison - Each strike with your weapon has a 30% chance to reduce your target's movement speed by a good amount (50% at the first rank, 70% at the second rank) for 12 seconds. A terrific PvP tool, as well as being useful in PvE when fighting Humanoid mobs that will run when low on health. May be trained at levels 20 and 50.
Mind-Numbing Poison - Each strike with your weapon has a 20% chance to increase your target's casting time on spells for 14 seconds. Good in PvP against casters for obvious reasons, as well as some specialized PvE situations (some raid bosses, caster mobs). May be trained at levels 24, 38 and 52.
Wounding Poison - Each strike with your weapon has a 30% chance of applying a debuff to your target that will reduce the effect of all healing abilities on that character by 10% for 15 seconds as well as dealing damage. It will stack up to five times. This poison is now _incredibly_ useful in PvP (when fully stacked it has the same healing debuff as Mortal Strike, and stacking both on one target - such as a Warsong Flag Runner - is incredibly effective) and the addition of damage (around a third of Instant Poison's damage, admittedly) makes it useful against non-healers as well. May be trained at levels 32, 40, 48, 56 and 64.
FAQ:
Q: Can I apply poisons to the weapons of other players?
A: No.
Q: Can I use both a Sharpening Stone and a Poison on the same weapon?
A: No. Each weapon has a limit of a single buff, so you cannot have use both poisons and a sharpening stone on the same weapon - the buff will overwrite whatever was already on the weapon.
Q: Help! I can't train in [Generic Poison, but usually Mind-Numbing Poison]! It's not on the list of abilities from my Rogue trainer.
A: The reason is because you need a specific skill to train in poisons, so if you haven't created enough poisons you won't be able to learn that ability. In most cases the problem is with Mind-Numbing poison, which requires a Poisons skill of 100 to learn. After Mind-Numbing Poison you won't usually notice this limitation, but it's an issue in this case because it's quite likely that you won't have created 100 poisons between levels 20 and 24, and that's assuming that you did the Poison quest as soon as you possibly could.
Q: Do you know where I can the stuff to make Blinding Power?
A: Well, it's not really related to poisons, but it's still a good question. Blinding Powder is created from Fadeleaf, so you'll need to find a Herbalist (or be one yourself) to get the regent for the Blind ability.
Q: Why is Crippling Poison II worse than Crippling Poison I?
A: It's not. The problem is that Blizzard changed the format of the spell effect. Crippling Poison II is better, go and read them again.
Q: Can I apply a poison to an enchanted weapon? Will it overwrite the enchant?
A: No, it will not. Go ahead and Crippling Poison up that Dagger of yours if you want, it won't overwrite the enchantment placed on it.
Edited, Tue Jul 19 12:11:31 2005 by RPZip
Edited, Tue Jul 19 16:21:03 2005 by Darkflame
EDIT: Looked at this thing again and realized that I screwed up one of the tags... whoops.
Edited, Sep 9th 2006 at 2:18pm EDT by RPZip
Edited, Oct 23rd 2006 at 3:59am PDT by RPZip
EDIT: Updated for TBC.
Edited, Jan 14th 2007 6:09pm by RPZip