You can send this card to the GY; Special Summon 2 Level 3 or lower Beast monsters from your Deck, but their effects are negated, also they are destroyed during the End Phase. You can only use this effect of "Rescue Cat" once per turn.
Rulings
Individual Card FAQs
If one of the monsters Special Summoned by “Rescue Cat”'s effect is flipped face-down, or removed from play temporarily, the effect of “Rescue Cat” is reset and that monster is not destroyed during the End Phase.
If your opponent controls your “Rescue Cat” and activates its effect, your opponent gets the effect and Special Summons Beast-Type monsters from his/her Deck.
You can activate the effect of “Rescue Cat” even if there is only 1 or zero Level 3 or lower Beast-Type monsters in your Deck. However, in this case you cannot Special Summon any Beast-Type monsters for the effect of “Rescue Cat”, and your opponent gets to check your Deck to confirm.