What a big cat! My mother has a cat like that-- his name is Bustipher, and he's black like your Napoleon and similarly HUGE. Before he was even fully grown, stretching out on my lap from front paw to back toes he was over three feet long, and now he's even bigger! Picking him up is like hugging a small bear
I think the treat my mother's cats like the most is the birdfeeder she put up next to the windows. Both the stick-to-the-window kind and also the hanging-in-the-yard kind. Her older cat especially likes to sit in her window seat and watch the birds. She makes those clicking noises and tiny threatening mews. She doesn't enjoy playing much, but apparently nothing beats telling the birds to get offa her lawn!
My cats like hideaways. My apartment is small and I move a lot, so I don't have a cat tree, but a cardboard box upsidedown on the floor with a couple of doorways cut out of the sides is plenty of fun. Good for hiding in, and also good for sticking paws out of to give stealth-swats to passersby. Also, they gnaw on the sides of the doors.
Small pots of catgrass are always appreciated. Decorate a pretty pot and plant some whole wheat or rye berries in it. You can usually find them in the bulk section at the grocery store. I think uncut (and obviously unrolled) oats may also work.
Hope you find something he likes!