Elemental HERO Air Neos

Level 7 WIND/Warrior Fusion Effect
2500 ATK / 2000 DEF

"Elemental Hero Neos" + "Neo-Spacian Air Hummingbird"
This card can only be Special Summoned from your Extra Deck by returning the above cards you control to the Deck. (You do not use "Polymerization".) While your Life Points are lower than your opponent's, this card gains ATK equal to the difference. This card returns to the Extra Deck during the End Phase.

Rulings – Yugipedia

Printings:

Strike of Neos: STON-EN034 (Ultimate Rare) - 2007-02-28
Strike of Neos: STON-EN034 (Ultra Rare) - 2007-02-28

Prices:

Cardmarket: 47.22 €
TCGplayer: $ 185.72