Not only does the card immediately replace itself, but it turns on lots of powerful synergies across the Sapphire color

Final Fantasy Main Set $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 Extended Arts $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 Borderless $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 Starter Kit $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 Final Fantasy Through the Ages Main Set $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 Secret Lair Final Fantasy: Game Over $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 Final Fantasy: Grimoire $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 Final Fantasy: Weapons $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00 $ 0.00

Other cards like Goblin Tunneler and Rogue's Passage that make creatures unblockable are also fairly great options with little investment, with Jumbo Cactuar seeming to pair pretty excellently with both red and green spells respectively
I see her fairing better in the long run, however, than the location/song cards on this list given her status at Disney Princess
Three Strength is a big win for Peter Pan, too
Gilded Lotus Now, to one of the more contentious entries on this list