Rainbow Dark Dragon

[ Dragon / Effect ] (This card is always treated as an "Ultimate Crystal" card.) Cannot be Normal Summoned/Set. Must be Special Summoned (from your hand) by banishing 7 DARK monsters with different names from your GY. You can banish all other DARK monsters from your field and GY; this card gains 500 ATK for each card banished this way. ATK/ 4000 DEF/ 0