There's an absolute ton of pre-requisites to getting the Magus Sisters, including:
- Getting Yojimbo (substantial sum of gil needed, plus completion of Sunken Cave sidequest)
- Getting Anima (all Cloister treasures needed, plus defeating Geosgaeno, in PAL/INT versions can necessitate defeating Dark Valefor/Dark Shiva if Besaid or Macalania treasures were missed first time around)
- Riding a chocobo to Remiem Temple from the Calm Lands
- Defeat Belgemine's Aeons up till Bahamut (I think) to receive the Flower Sceptre
- Capturing 1 of every fiend in Mt. Gagazet to get the Blossom Crown (requires capturing 1 of every fiend in the Calm Lands first)
Just something I thought of. But I don't remember there being anything particularly noteworthy about receiving them, other than allowing you to send Belgemine if you beat her Magus Sisters afterwards.
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