on TBC 2.4.3 people were using WPE to polymorph themself to pig and get 1000hp/sec .
But there in wotlk (i tested it on 3.0.0 to 3.0.9) when enemy mage polymorph you to pig, you get 1000 hp per second It work on all versions, i think, because people dont know how to repair it.
its working on ascent on mangos - idk...
it can help you fight in BGs.