Amphibious. If the Form has a swim speed, the Druid can breathe both air and water.   Flyby. If the Form has a fly speed, the Druid doesn't provoke opportunity attacks when they fly out of an enemy's reach.   Keen Hearing and Smelling. If the Form has no fly or swim speed, the Druid has advantage on Wisdom (Perception) checks that rely on hearing or smelling.   Bulky. The Druid has +2 damage on attacks and +1 additional temporary hit points per Druid level (5+2xDruid Lvl).