Jumbo Flan is a special enemy in Final Fantasy X. It is bred in the Species Conquest section of the Monster Arena once three of each type of Flan-species fiends have been captured. It shares the same model as the Dark Flan.
Jumbo Flan is immune to physical attacks and absorbs all elements (except Holy). It has Reflect that cannot be dispelled, but it is susceptible to Slow if the player bounces the spell off a party member (the member must have Reflect status).
When it uses Regen on itself it only lasts 10 turns.
When farming Jumbo Flan for Magic Spheres, the player will want to kill it as fast as possible. The fastest strategy initially is to max out Yuna's Magic Defense and Agility, therefore maxing Anima's corresponding stats as well. Anima should know Haste, Shell, Lancet or Curaga, and Dispel. Regen is also useful here.
The player should start by casting Reflect on one party member and bouncing Slow off of them to slow down the Flan. The player can then summon Anima and buff her with Haste and Shell, as well as optionally five boosts of Focus, for both fortified effects of cure spells and reduction of Jumbo Flan's offensive spells. After that Anima should use Pain 2-3 times, depending on her agility, each turn. If Jumbo Flan uses Regen it can be dispelled right away, but if the Pain attacks are doing enough damage the effect may be insignificant.
If using a regular party, the battle should still be started by slowing down Jumbo Flan. The party can then cast Haste, Shell and Focus on everyone (and dispel any characters of Reflect). The party should Doublecast Flare (preferably) or Ultima. Holy also works, but cannot be doublecast.
The characters that should be used are Yuna and Lulu who boast the highest magic power. Lulu's fully powered Celestial Weapon also offers Magic Booster and One MP Cost effects, which are perfect for this battle, and if one received Dark Matters from catching monsters for Arena, another weapon can be created with Break Damage Limit, One MP Cost, and Magic Booster.
Overdrives are effective because they are neither physical or magical, but due to Jumbo Flan's defensive stats, their damage is significantly reduced when compared to spells or Anima's Pain attack.
Flan is an open pastry or sponge cake containing a sweet or savory filling. A typical flan of this sort is round, with shortcrust pastry, usually coated with sweet syrup. It is similar to a custard tart or a South African melktert.