First strike works the same way whether a creature is attacking or defending
The Reaper is certainly a powerful Commander if you wrap your head around your -1/-1 strategy, but I do think Auntie Ools card draw is the more compelling feature, as you might even be able to draw The Reaper, and other synergistic cards, by exploiting your Ward/Blight abilities
Leshracs Sigil Leshrac's Sigil makes me happy because of the parallel casting cost and activated ability costs
Cards like Black Lotus, Ancestral Recall, and the Moxen are not only incredibly powerful but also steeped in history
Fun Fact : After this are cards that are literally worth more than their weight in gold at the time of writing
This influx of interest in fake cards has pushed the counterfeiters to new heightsjust look at the "progress milestones" of one major counterfeiter above