War Rock Generations (LIOV-EN091) [Lightning Overdrive]

During the Battle Phase, if your opponent controls more monsters than you do: Special Summon 1 "War Rock" monster from your Deck, and if you activated this card during your opponent's turn, for the rest of this turn while you control the face-up Special Summoned monster, your opponent's monsters cannot attack, except to attack that monster. You can only activate 1 "War Rock Generations" per turn.