How to Metagame for New Players

I love in combat to just bust out scary moves in the first round. It puts your players in a place of like, oh, yeah, like we're confident and it's one against four or we got this. And then the monk teleports across the room, grabs you and spins you around and throws you against the wall 15 feet away. You're like, hang on. Wait, what? I'm not a monk. I didn't read that class. Or do I spend my turn running away? Or do we just try to fight this out and hope we can win? Even if they beat him, nobody got super badly injured. They were able to beat him, but like