is it possible to say something bad about a stock on twitter and make it's stock drop, and what are the legal implications?

If I were to say something bad about a very small company traded on the stock market on twitter could that end up dropping the stock price of that company, even if just for a single tick?
Then if I were to go buy that company up at that lower stock price and then immediately sell once it goes back up, would that be illegal? Like market manipulation or something

edit: for context im talking about my twitter account which has maybe 12 followers with a demographic that would think i would have gotten hacked if i randomly started spewing nonsense about random companies