S1·E24 Expert's Beginning Knights

Beginner brings the Mon Colle Knights to a monster summoning school where they could learn to summon monsters to help them out. They find Lele delivering a bunch of Lemmings somewhere and also encounter Luke, a boy who's secretly in love with Beginner, and his sheep Lambda. Meanwhile, with Tanaka on vacation, Prince Eccentro takes control of a Horned Beetle to destroy the school and the cage where the Lemmings are held is in danger. The Mon Colle Knights merge with a Lemming to help the other Lemmings escape and defeat Prince Eccentro with the Horned Beetle (NOTE: Lemmings may be small, but they're very strong).