XYZ-Dragon Cannon [BPT-010] Secret Rare

X-Head Cannon + Y-Dragon Head + Z-Metal Tank This monster can only be Special Summoned by removing from play the above monsters on your side of the field. You do not use "Polymerization" to Special Summon this monster from your Fusion Deck. Discard 1 card from your hand to destroy 1 card on your opponent''s side of the field.