With so many ways to play for so little a cost, it’s hard not to recommend Dr. Luigi. The Dr. Mario gameplay has held up over the years because, like Chess, Checkers, or Don’t Take a Whiz on the Electric Fence, it’s easy to pick up but constantly shifting. Plus, it only costs fifteen bucks to download Dr. Luigi, which, given the amount of replayability here, is a friggin’ steal. If you’ve got a fever, you know the prescription. No, it ain’t more cowbell. It’s more Dr. Luigi.