That's just inefficiently stupid. Don't burn bridges, burn entire cities.
If you want to go down the blunt force road, don't down vote manually, let a script do that ... for you and your 10 closest ~~alt accounts~~ friends.
If you want to be a bit more sophisticated you have a bot run your alt accounts, commenting with short LLM generated content at random posts. And whenever your mark is active, you use one of these accounts to come at them. Maybe have your replies rewritten by your AI, so you don't give it away by using the same phrases.
You can take it one step further, and analyse your marks interactions. Does a username pop up more than others consistently? Then your mark may have both poor OPSEC and an alt.