Fusion Dragon Invasion

You can only use this Skill's first effect once per Duel. 1: If only your opponent controls a monster, play 1 "Predaplant Chlamydosundew" to your field from outside of your Deck in face-down Defense Position (its battle position can be changed) and place 1 Predator Counter on 1 face-up monster your opponent controls. Any monsters that are Level 2 or higher become Level 1 as long as they have a Predator Counter. During this Duel, you cannot Fusion Summon any monsters, except DARK Dragon monsters until you Fusion Summon a DARK Dragon monster.