onslaught booster box Cardfight Vanguard Overdress: BT12 Evenfall and existing tactics will evolve. Gate Ruler TCG Booster Volume

This 6/6 Beast for was already under curve for the time, but then you tack on an easy-to-ping triggered ability and two useful activated abilities and you're looking at a Morphling-level creature (for the time)

These tell what the energy cost of the attack are

C Common Numeron Creation X SPELL (This card is always treated as a "Galaxy-Eyes" card.) If 3 or more LIGHT Dragon monsters with 3000 or more original ATK are on the field: Special Summon 1 "Number" Dragon Xyz Monster from your Extra Deck, then attach this card on the field to it as material

That wraps up our picks for the rarest and most expensive Pokmon cards in existence