You probably know the situation: You want to kill one of the murlocs, and they all attack you at once.
If you are a hunter or a rogue (perhaps other classes), there are means to avoid this. Some say this is common knowledge. I only learned about it, when my hunter was almost lvl 78. So common? Perhaps, perhaps not.
What you do is to set up a frost trap near the group of targets.
Then you aim and fire at the mob/beast, you want to kill.
Immediately, he will start running towards you and bring his pals. He hits the trap and freezes.
You should now use Feign Death, and all the mobs will return. Also mr. Frozen.
Then very quickly you make your move, because your orignal target will be a little bit ahead of the others, and now you can shoot at him, without attrackting the other mobs.
For rogues you should be able to use Blind Evasion to do the same trick.