As a general rule of thumb, I found that for madness cards, the cheaper the madness cost the more appealing the card
At best, you wipe up an aggro decks board, get rid of some cards which are useless or bad in the matchup, and have a great body when it's done resolving
Lorwyn Eclipsed Set Review Ben Guilfoyle previews Lorwyn Eclipsed: products (Play/Collector Boosters, Bundles, Draft Night, Prerelease), headline mechanics (Kindred, Evoke, transforming DFCs, Blight, Vivid), supporting tech (Persist, Convoke, Behold), Commander reprints and precons (Elementals, Blight), new fetchable duals, plus early chase cards for brewers
The best reason to splash an additional color