I need help choosing my last two party members. I plan on using Serperior, Krookodile, Simipour, and Archeops. Right now I also have Tranquill and Munna. I want to choose two out of three from Axew, Tynamo, and Litwick. I know Tynamo and Litwick are both fairly weak and evolve late but I know their evolutions are very good. Suggestions?