Oath does lead to some interesting interplay as you can force them into killing their own guys or not playing any
I bring it in against all the midrange and control decks out there, where it removes a difficult to kill threat and returns a glorious win condition to the battlefield
Getting into your graveyard is also crucial, if youre on a reanimator plan
(9/25/2006) If either target is illegal at the time the ability resolves (whether because it has left the battlefield, because it has gained Shroud or Protection, or for any other reason), the ability taps the remaining target, but no damage is dealt
There is, however, one major catch to the arrival of these cataclysmically powerful cards
Cathartic Reunion is especially important as it allows you to first discard some Dredge cards from your hand, and then draw cards, but replacing each draw with Dredge 3, 4, or 5