I complained to the landlord and was unheard, I complained to them and they said "ok" and continued. Several complaints later I threatened to call the cops, it was a proper house party, middle of the week, they were clearly crackheads with no jobs, there was tons of people, alcohol and drugs.

This was their very first night.

Since then we interacted many times, all of them extremely unpleasant. It eventually evolved into a war where I would bang on the ceiling at random times of the night, and I hooked my guitar amp up and blasted music directly into the ceiling all day and all night until they came down and started bitching that all of this was giving them panic attacks. That felt satisfying!

Eventually I managed to get the landlord to agree to evict the fuckers, due later this month, hopefully the leech follows through. We secured a temporary truce but they've been getting more and more brazen with their noise levels, I've placed the amp back up to the ceiling so it's ready for the right moment to start blasting.

Some other ideas I had is spam deauthing their WiFi.