Definitely of mythic rare quality and a limited bomb as it masquerades as a Timmy card while truly being Johnny in disguise. It's also probably 1 colorless mana too much. That being said, just like Undead Alchemist begs for it to be paired with other stand alone, offensive mill spells, Drogskol Reaver begs to be paired with as many life gain spells as humanly possible. As far as I'm concerned, it's a good day to be a magic player when the designers of the game make cards much more open ended. Consider the following card:
Flying, double strike, lifelink
Whenever Drogskol Reaver deals combat damage, draw a card.
The people at Wizards could have easily made this card that, but they didn't. They could have limited it to combat damage and only damage from Drogskol itself, but they didn't. They could have done that and all the Timmy's of the world would still have praised it as a flying, double striking, lifelinking fatty... and all the Johnnies of the world would pause a moment to try and figure out if it's worthy of running in their latest Reanimator Deck and then move along. But because they decided on its current open ended design, the Johnnies have much more to think about and I can go to sleep happy this day.
It's also important to note that this card is a bigger deal in Innistrad Block than it is in other formats. In Innistrad, the only reliable forms of permanent card draw come from Mentor of the Meek, Sturmgeist, Bloodgift Demon, and to a lesser extent, Charmbreaker Devils. Drogskol Reaver not only is an additional card drawing option, but the amount of cards you'll be drawing from this versus the others is a big difference.
You can actually go so many directions with this card that I don't actually know where to start. You either build a deck filled with lifelinkers on the back of a mana curve that tops of at Drogskol Reaver or you strip the entire deck from all creatures except for 3-4 copies of Drogskol Reaver and fill out the rest of the deck with life gaining instands and sorceries or you try to force it into some wonky reanimator/hybrid.
Personally, I'd think focus on ways to make the most use of the cards you'll be drawing. My mind first goes to cards like Reliquary Tower and Spellbook and then it goes to other things like Empyrial Plate and Ivory Tower. Fun stuff.