Reference article
Super Seed (Duck Life 2)
Purple food that raises energy by 3 levels without increasing racing skills.
Buying and feeding
Buy the purple seed from its home-screen dispenser for 15 
Coins. Eating it raises 
Energy by 3 levels. These effects apply in original Flash and later editions.
Naming and comparison
Super Seed is purple and improves energy only. In 
Duck Life 1, the blue 
Skill Seed also raises racing skills in original Flash.
Value
Five normal 
Seed give the same energy increase for 5 coins. Both food types are subject to the current Maximum Level Upgrade.
Across the games
Compare games and editions on the Skill Seed page.