Greninja (41/146) [XY: Base Set] WTR018-R Then return the same number

Then return the same number of cards from the field to the hand

Both players then pick up 5 cards from the top of their respective Decks and Special Summon all Level 4 or lower Monster Cards among them on the field in face-up Attack Position or face-down Defense Position

you can discard up to 2 cards to the Graveyard to select the same number of cards your opponent controls

When this card is sent from the field to the Graveyard: You can add 1 "Frog" monster from your Deck or Graveyard to your hand

when resolving the effect

Greninja (41/146) [XY: Base Set] WTR018-R Then return the same numberSet: XY: Base Set Type: Water Rarity: Holo Rare Retreat cost: Colorless