I had a colleague that ended up in a mental hospital for a while after their boss bullied them for a few years and flashed colleague's major achievements to own

I had a colleague that ended up in a mental hospital for a while after their boss bullied them for a few years and flashed colleague's major achievements to own bosses as their own. The colleague didn't like their boss for sure. I guess that might be one hint to "tyrant boss"? Would that work for you?