It took me three tries to get this.
You have to move. When Yda/Papalymo say that you should focus on the sylphs and leave the morbol to them, that's your cue to drag the sylphs away from the morbol. The adds will come to you and ignore Yda. Yda and Papalymo can take care of themselves.
The morbol has an AOE status effect of poison/slow/god knows what else, and if that lands on you you're going to die. Get yourself out of range of the morbol, but not out of range of Papalymo's cures, then you can just focus on the sylphs.
Also, if a sylph is taking a long time to go down, that's the GLD one. Change your target to one of the squishier ones to get them out of the way.
____________________________FFXI: Catwho on Bismarck: Retired December 2014
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