My power is 412,549. By myself, I oneshot rogue ninja using my kisame team.

When one of my friends join me, he is 100k higher than me, I still oneshot the rogue ninja. He will be afk and doesnt auto, so Im still attacking and still one shot. Now sometimes another friend joins and he is 1m in power, so his initiative will be way higher than mine. He wasnt one shotting, so my question is, when your in a team, do the rogue ninja get stronger. And do they get stronger depending on the teams power. Like my friend that joined was 1m, so they got much stronger. Is that how it works?