Stone Camouflage. The giant has advantage on Dexterity (Stealth) checks made to hide in rocky terrain.
Multiattack. The giant makes two greatclub attacks.
Greatclub. Melee Weapon Attack: +9 to hit, reach 15 ft., one target. Hit:19 (3d8 + 6) bludgeoning damage.
Rock. Ranged Weapon Attack: +9 to hit, range 60/240 ft., one target. Hit:28 (4d10 + 6) bludgeoning damage. If the target is a creature, it must succeed on a DC 17 Strength saving throw or be knocked prone.
Rock Catching. If a rock or similar object is hurled at the giant, the giant can, with a successful DC 10 Dexterity saving throw, catch the missile and take no bludgeoning damage from it.
Standing twenty to thirty feet tall, giants are towering bipedal creatures that follow the flow of aether on regular migratory routes. Once they start moving, they build both momentum and a single-mindedness that makes them nearly impossible to stop. Anything in their path, whether it's a building or a force of soldiers, is crushed without thought.