As a mono-dark player like me, this card is just what I needed to take out Elite Otyughs AND Firefly Queens. It's almost my only way to salvation in the Top 50 against people using those, as the AI will instantly beef them up in the same turn they put them into play possible, rendering Drain Life useless.
Of course, when your opponent won't pull out any of that, Black Dragons are the optimus candidate. Thanks to this card I end duels with 100 HP quite more often.
So, thanks for the card!