Corrosive Scales (Common)

Target 1 Insect monster you control, equip this card to it. While you control the equipped monster, your opponent's monsters cannot attack Insect monsters, except the equipped monster. While this card is equipped to a monster, each time your opponent Normal or Special Summons a monster(s), OR activates a card or effect, place 1 Scale Counter on each face-up monster they control. Each monster your opponent controls loses 100 ATK/DEF for each Scale Counter it has.