Fight starts out simple enough, just a strait boss with a somewhat extreme knockback. Your tank will need to find a good place to stand. The outer walls are somewhat problematic, as he knocks you all along the wall. The flaming pots work ok.
After a period of time, he is going to drain nearly all of your power, down to around 10 or 15%. He will continue to do this periodically throughout the fight.
He will also begin popping adds, called Mana Souls. These adds have approximately 2 million HP, and must be killed in 20 seconds. Failure to kill them in time will have Treskar eating them, and healing himself 15-20% in the process. The adds also mem wipe, just to add a little more fun.
Monger Fist is a nasty trauma on a 45 second timer with a power drain attached. (first hit is around 45 seconds into the fight, not interruptable) Turnstrike and Sever Hate both allow this to be avoided, so I assume things like Bladedance and Tortise Shell would work as well.
That's pretty much the fight. Chanter is working his butt off to keep power up on the group constantly. Kill the adds quickly.
Final note: Treskar cannot die if a Mana Soul is up! Do not try to push through if a Mana Soul pops up while he is extremely low on health.
[media]http://www.youtube.com/watch?v=98qQareQj4M[/media]
If a Moderator wants to add this video to the strats that is cool =)
There is no way to do the zone with 12. It is only available to a single group, thus why when the mobs are x2, it's "hard mode".
just a short question: is the hardmode of that zone intended to be done with 2 groups (cause its listed here as "x2")?
Someone ever tried to zone in with more than 6 ppl?
Thx 
The best place to tank this mob is on the lvl below, in the area in front of where the first mob stands, if you stand between the two torches that are in the middle of the wall below the lift you will have no problems with any KB at all.
Pulling him is a matter of having grp stand in the place where they are going to fight, and having tank go up the elevator and pulling named just before (or just after) he throws the lift lever to descend and getting back into heal range as fast as u can b4 yr hit blocks wear off.
You cannot turn this mob into x2. You must turn the first mob in the zone x2, and then all subsequent mobs will be x2. If you kill the first mob heroic, the entire zone will be heroic.