Still a bit of a mystery, never done it myself . This is what I can gether so far:

Firstly you need someone who can take alot of heat, i.e. Bio Sheild / TMS toon etc... etc.. BUT must also be able to land a DOT on your selected target.

Ring of Putrescent Flesh, something I picked up in IS, seems to land on anything. Its a Chemical DOT. Nano Fingers also work well.

The next bit Im a little fuzzy on, so if anyone wants to comment please do.

Once the DOT has landed, from what I can gather you die.
When you re-zone out of the Garden the mob warps to you.

Another neat trick is CH'ing without aggro'. If your near a 100%/75% border, have your doc' stand in 100% whilst you fight the mob in 75%. That way your doc' can CH without the risk of aggro.

After the patch the bosses seems to be static ... that means - like tara ... they do not move, you have to kill them at their position. We tried diffrent tactics with ~25 people today but no one seems to fit. If there are any tricks pls share them with the community.

tested it after patch , no changes , respawn 4 minutes and the Zodiacs warps.

 :|

btw. which mob @IS drops the "dot ring" ?

 :'( Me too man... I haven't touched AO in years ! Life got a little choatic, and I moved to the US of A ! It's great to come back and read this stuff though, I can't believe the forums are still running !