When I first looked at this card I had to read the effect twice to believe it.  In addition to the effects of the equip card you also get an extra 500 attack points.  If you equip something to it that wouldn't normally do anything you get 500 points anyway because of the effect.  This is probably the most powerful 4 star in the entire game.  Imagine equipping a Malevolent Nuzzler to it.  The equip card and the effect combined increases it's attack by 1200 points.  That's a 2750 attack!  Thats stonger than some 7 star monsters.  If you find it it is a must to put in anyone's deck.