As they attempted to retreat, Bronn was also in charge of trapping them in place by linking the chain across the water and preventing the navy from falling back.

Source: https://gamerant.com/game-of-thrones-bronn-fate-explained/

If a scene is too heavy or there's an extended moment of tension, Bronn will bring things back to normal with a funny quip.

Source: https://collider.com/game-of-thrones-funniest-characters-ranked/