Peanut
The Peanut is a Tier 6 Food, but isn't normally available in the shop and can only be obtained through abilities. Whenever a pet with Peanut perk attacks and hurts an enemy, the enemy will be instantly knocked out.
Strategy
Peanut acts as a special counter against scalers. Once hurt, regardless of how beefy the enemies are, they will be instantly knocked out by Peanut.
The pet with Peanut perk only really has to care about health. The longer it survives, the more likely it is to knock out more enemies. However, the enemy needs to be considered "hurt" in order to be knocked out. So against 
Melon, the pet with Peanut needs to have 21 attack or higher to break through the Melon and knock them out. Peanut will always lose against 
Coconut.
An ideal Peanut pet stays at 21 attack, and does not need to be scaled any further. The more stats it receives, the less effective Peanut is. At certain point, it won't be any more useful than other food perks.
A special interaction is against 1 health enemies with 
Pepper. The Pepper will keep the enemy at 1 health, they will receive 0 damage and won't be knocked out by Peanut.
Obtaining Peanut
Scorpion comes with Peanut and is the most common Peanut pet.
Knocking out a 
Walrus during shop phase will give random pets permanent Peanut. Giving pets 
Donut before knocking out the Walrus to guarantee them receiving the Peanut. Target a 
Seagull or 
Chipmunk in order to duplicate more Peanuts.