You dont need to be super stealth to catch this Ninja. Your cat will be leaping, kicking, and pouncing for joy as they chase this little ninja two pack with enticing crinkle sound! It's filled with a custom blend of tempting catnip and silvervine for twice the cat attractants. Silvervine is an all-natural catnip alternative that cats love. It elicits a similar reaction to catnip and works for many cats that are not normally affected by catnip.