One of the Hunter's greatest attriutes is the freeze trap. This is THE most versatile crowd control in the game. ANY mobs that can be crowd controlled can be trapped (unless they're immune to ice) and in addition, traps are not currently subject to diminishing returns. They last for the same amount of time every time they trap something (once again, this depends on resistances).
The problem is, many hunters never bother to learn how to do this, in part because it takes effort, and in part because most parties would rather rely on a method of crowd control that's easier to use.
Here are a couple of my tips on how to chain trap effectively:
First and foremost, set up your traps away from the main area of combat. this allows tanks to use AOE, and makes it easier for you to see what's happening with your target. This will likely hurt your DPS on the meters, as you will be running back often to get something trapped. This is OK. if you've been assigned a trap target, keeping it in control is your PRIMARY concern, because if it breaks and you wipe, that's your fault.
The next trick is to set your trap early, so that you won't be waiting on cooldowns. Survival hunters have the advantage of a cooldown that's shorter than trap duration, so you can retrap before the trap breaks. Everyone else has to start, and stay head of their cooldown. This means laying the trap early, moving far away from the mob once it's trapped, and then putting your trap down as soon as the cooldown is up.
A couple other tips:
Distracting shot does no damage, so you should either make a macro, or learn how to hit a trapped mob with distracting shot without auto-shooting it (moving while you shoot is one way).
Feign death AFTER your tank taunts (if it's a warrior). this will take you off the aggro tree, of course, but it will let the warrior get ALL the aggro you've built up, and give him an edge on the DPS.
Also, it IS possible for a survival hunter to chain trap two mobs IF he has enough armor or kiting ability to let cooldowns finish. This takes a 26 second head start (for the cooldown) and some fancy footwork. Try for it with a friendly group some time, and good luck.
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