While transforming cards are creatures on both sides, MDFCs can be all kinds
Like most Pokmon cards, the value of Jigglypuff depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (Paldean Fates)
It represents a collision of fine art history and pop culture that simply has no precedent in the Pokemon TCG
If you have "Puzzle Reborn" Set when activating this effect, you will be able to Special Summon the monster you just destroyed with the effect of "Fire King Island"
Its limited supply and price range between $89 and $1,000 make it an attractive option for collectors
Instead, another effect sets them up to trigger later