When exactly 1 monster with 1500 or less ATK is Special Summoned to your field while your opponent controls a face-up monster: Special Summon as many monsters as possible with the same name as the Summoned monster, from your hand, Deck, and/or GY, in Attack Position, also your opponent Special Summons as many monsters as possible with the same name as 1 of their face-up monsters, from their hand, Deck, and/or GY.