Both of mine are clever. And they work together. The fridge now has a lock on it, but when they worked out how to open it, blond!cat would sit on the worktop beside it use a paw (& claws) to tug at the seal until it gave and the door could then be pushed open by joint effort, with black!cat at work on the floor. Black!cat would, once the door was open, sit and act as a doorstop, allowing his brother to climb into the fridge and thoroughly examine the contents; lobbing out anything that smelled worth pilfering. They had learned this need for somecat to hold the door open after they, as tiny kittens, worked out how to get into the food cupboard & promptly got stuck, which ensured they were immediately rumbled. I mean, the tiny toothmarks in things would’ve done for them very swiftly anyway, but…
They have a propensity for rootling through the recycling but also for bashing bins about the place. Stealing whatever human food they can get is rather a passion project; & my black cat has learned to unzip bags to this end. I’m a vegan, but from the way they go after my food you’d think the cats were mounting stealth raids for tuna not tofu (etc).
My blond cat figured out the idea of fetch by himself & will come & ask me to play it with him.
Essentially, they are Mischief On Legs, but happily they are also The Snuggliest Cats EVER & as I’ve mostly been in bed for the last couple of years, there’s more snuggling than havoc-wreaking these days. Though they do still go on the occasional rampage, important to keep one’s paw in, after all 