things that have so far completely failed to keep Sumo from climbing up my TV and threatening to destroy it

- yelling

- putting him in time out instantly every time he does it

- putting foil up on the top of the TV

- providing an alternate route up above the TV

I'm running out of ideas

Amazon.com : XFasten Clear Double Sided Sticky Tape,...

I've never found foil helpful, but

double sided tape

oh i forgot i had [ clap ] as an actual emote

it also has the upside of being sticky so cats can't just like.... knock it down. it's also harder to ignore. AND it can be put up on like doors or corners if the cat starts scratching those.

If I read your earlier illustration right the TV is in a piece of furniture that has a shelf above it. Can you, like, fill the gap between the top of the TV and the bottom of the shelf with something so Sumo has nowhere to go? (Though securing it so he can't simply knock it out of the way may be difficult...)

it's about an 18 inch gap so I have no idea what I would put up there

possibly you could get creative with small boxes or styrofoam chunks

though yeah I'd say go for double sided tape next, and/or the motion-sensing air blaster

tape prob cheaper to try first

where would I even put thet air blaster

next to the TV

there's some space to either side, right?

Tape the air blaster to the bottom of the upper shelf!

(It's probably too heavy for that)

Tape styrofoam to Sumo

is there anywhere else that Sumo can go to be High?

he can climb the cat tree to go directly up to the platform that's over the TV