The actual term "multiattack" only shows up in the PHB a few times, but it never indicates whether the subsequent attack is restricted to the same target as the first one. Because it is never explicitly stated I assume that multiattack can indeed target different opponents with each attack. Please correct me if I'm wrong.
Following this logic brings me to the question of whether each of the multiattacks can be separated by movement. As in, a Brown Bear attacks a Wizard in range with his Bite attack, moves 30 feet to get beside a Fighter, and then attacks the Fighter with his Claw attack.
Is this how multiattack is meant to work?