Pretty much what everyone is saying here, Wafik said what I was going to post for the most part.
JoL you need 3 things:
1) Stable Tank party.
2) Way to kill/hold the Summons
3) Way to Damage JoL
Really doesnt matter what method you use for each as they are all independant of each other.
Our prefrence for tank party is Aegis/rdm PLD/rdm Ghorn/whm RDM/whm WHM/smn
2 Tanks stand side by side with a little distance maybe 1' between them, yeah they both take all the aoe, but this actually helps them to have somthing to sink more MP in with C4. We stand them outside the den, they stand just on the Den's side of that little ridge you cant quite walk over correctly. If you go to the JoL area, you will be able to see what im talking about, its just about max range before Draw in.
Just last night we had a goofy situation where the tanks got a little to close together (think they were bored and /dance4 while tanking) and Airel Collision x3 took both out at once, we quickly had the tank pt RDM take over tanking. even if JoL goes a little wild, hes not that hard, as long as your Summon killers are up and able, JoL is not much more then a slow fat kid trying to throw haymakers at you.
Our perfered method to kill sharks is BLMs -ga. We have done this mostly just with blms and a brd in that outside allaince. We have used a PLD/WHM a little if we have extra bodies to diaga the adds to the blms, but thats only for those freak times when DD seem to pull hate just as they pop and the adds stand on the DD and chomp chomp.
For Damage we have done a lot of things, we use to rotate DRKS with SE M.kris and K.Club this is great for fast damage but typically the Tanks have no way to keep the DRK form eating it after a couple cycles. For the last 8-10 JoLs we have just been stright up TP burning it. Grab a bunch of 2hand wep ppl, stick them under it and let them smash it. Our 2nd run last night took about 1hr 5mins with just an assortment of DDs, we had 18 in main allaince, all but the tank WHM were outside curing. We didnt have any where near optimal setup, we just let some ppl come play. We has a couple extra DDs waiting for JoL to gank ppl to get rotated in also. Our SAM/THF was assissinating others 1 by 1 so we could rotate in people XD.
Also THF & Collorabrate(sp) for high DoT DDs (SAM) or having your big /thf WSs TAed onto a DRG to super jump the hate works well to keep JoL off the DDs.
with 25 your numbers are fine, we have Killed it with 28 last night which was overkill, and we have killed it with as little as 16 + 1 dual box BRD for outside blms and 1 dual box TH4.
Overall JoL is actually imo one of the easier and more forgiving fights in Sea.
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