[Armin makes a soft noise of assent. He really doesn't like sending pokemon in unprepared either. He'd rather bide his time and train up and overlevel slightly than to send in an underleveled pokemon without a strategy and have them lose the fight because he was impatient.]

Do you have any pokemon with poison type moves? Those would work great against Clefable. Plus if you can inflect poison on it, it'll lose health every turn even without you attacking.