Well, this last weekend I actually tried out this one, twice. We failed both times, but would have won the second one had our tank started using her potions earlier. So, here's some thoughts I have from my experience:

1) The HP drain is a HUGE threat on these guys. You can sit there and chip these away, getting them near death, and they can get one HP drain that will heal them back up to full. Seriously, the biggest threat from these guys is this one effect. The drain cures them 25 HP, which is bad considering the lesser crabs only have 25 HP to start with.
- Solution: Evasion gear. EVERYONE must have high evasion gear. You want them not to hit you with this at all because it seems to give them HP drain every time they hit someone.

2) The main crab (I forget his name- the one in the middle :-) has nasty water-based attacks. Not sure if Barwater is available at that level, but he can be silenced.
- Solution: Silence him. Either have a mage silence him, or have a NIN tank with the silence effect katanas kite him.

3) Each crab will likely get HP drain a few times no matter how high you get your evasion. Thus, attacking each singly doesn't work well (unless you have MNK's 2 hour).
- Solution: We found the best results came from binding one crab, while two people focused on the other smaller one (and the tank kiting and occupying the big one). These things really die quickly when you have two or more people on them.

Now as for my group, we had the following setup:
* MNK/WAR (me) - HP regen drink + Evasion food + 3xHi-Potions
* NIN/WAR - HP regen drink + Evasion food + 3xHi-Potions
* RDM/NIN - HP/MP regen drink + Evasion food + 3xEthers

The MNK equipped the level 20 ice effect knuckles. NIN equipped the katanas with silence effect. The RDM has two low delay daggers.

Start of battle, NIN takes the big nasty center crab off somewhere and keeps him occupied. If no silence katanas, the mage should silence this crab.

MNK takes the right little crab off somewhere and starts wailing on him.

RDM binds the third crab, and joins the MNK fighting the right one. They both kill this crab. Once it is dead, they move back to the bound third crab and kill it.

Once both lesser crabs are dead, they both join the NIN to finish off the big nasty crab.

Now, we would have won this one easily. Our problem was our NIN didn't anticipate how long it would take to use the Hi Potions. As a result, they didn't use them before they died. Had they only done that, we would have easily won (by the time they died, we already had the first two crabs dead).

Anyway... there's my "damn! so close" strategy that should work now that I know what to expect. After you guys try this with multiple RDMs, lemme know if you succeeded. :-)

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