Talk:Hate Cards/@comment-25061243-20140730033226/@comment-24923366-20140804200951

While Grendel isn't out and out stated to be a Hate Card, his effects work in such a way, specifically against Magic World. Spells can't destroy him or return him to the hand, which, at this point, makes him immune to every single Magic World spell in the game, from Oops! up to and including Power Ray Maximum. And the Death Curse, while also applicable to Adventurers, wreaks the most havoc on Magic World, as there are very few monsters that can attack it head-on, or without a boost from Martil/Stradivarius, which necessitates Link Attacks. On average, you'd be losing two monsters a turn (if you have that many to spare), and none of your strongest spells can even touch it.

It doesn't have the whole "attribute" thing going for it that Beowulf and Balmung do, but given its skills, it's obvious what it was designed against.