We use 2 RDM/NIN to tank it and with a bard and a whm for Stona and Erase when necessary other than that the RDMs are pretty much self-efficent. The RDM tanks will spam dispel anyways for hate and will also at the same time remove its buff of stoneskin.
We found it much easier to just silence and sleep the worms. Have the blms use the elementals as a MP bank to aspir until its out and just time nuke it. New one pops, just have a rdm sleep it.
Have your blms save their elemental seal to Sleep II it after it lands. Nuke it when it flies, and repeat. When low on MP, skip a round when necessary of nuking to just keep it asleep. Ideally we bring at least 6-8 blms.
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