Draft Pelin and Crow. Depending on what your first card is, just keep picking cards of that same color. Even when just advantaged by one or two strong cards, you can stop purchasing from the tavern at that point and then prey on the opponent revealing a power card from the tavern. It's really that simple. Basically no thinking necessary. Orgnum is far more complex than literally just buying red or purple cards. You'll be fighting above your weight class with zero issue.
Don't tank
"In future content we will probably adjust this model somewhat (The BOP model). It's definitely nice to be able to find a cool item that you don't need and trade it to someone who can't wait to get their hands on it." - Wrobel