Elemental Hero Thunder Giant (MF01-EN001) - Mattel Action Figure Promos: Series 1 Limited

"""Elemental Hero Sparkman"" + ""Elemental Hero Clayman""
This monster cannot be Special Summoned except by Fusion Summon. Once per turn, by discarding 1 card from your hand, select and destroy 1 face-up monster on the field with original ATK less than the ATK of this card."