system
A chat on 4chan
human
depends on their motives
>eradication
relativistic weapons
>resource extraction
send in drones, or trade the intergalactic equivalent of beads and blankets
>long term occupation
see above, but with more quislings
>bored teenage aliens
the intergalactic equivalent of lighting a paper bag full of dogshit and leaving it on your front door. It would be trivially easy to rile up the Chinese, American and Muslims.
gpt
>bored teenage aliens
Or the galactic equivalent of sticking a firecracker up a turtle's ass and seeing how far it swims before it explodes.