Monster Manual, page 171
Trampling Charge. If the gorgon moves at least 20 feet straight toward a creature and then hits it with a gore attack on the same turn, that target must succeed on a DC 16 Strength saving throw or be knocked prone. If the target is prone, the gorgon can make one attack with its hooves against it as a bonus action.
Gore. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 18 (2d12 + 5) piercing damage. Hooves. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 16 (2d10 + 5) bludgeoning damage. Petrifying Breath (Recharge 5–6). The gorgon exhales petrifying gas in a 30-foot cone. Each creature in that area must succeed on a DC 13 Constitution saving throw. On a failed save, a target begins to turn to stone and is restrained. The restrained target must repeat the saving throw at the end of its next turn. On a success, the effect ends on the target. On a failure, the target is petrified until freed by the greater restoration spell or other magic.
Forest, Grassland, Hill