Siege Tower
Huge object
Armor Class: 15
Hit Points: 150
Damage Immunities: poison, psychic
Trebuchet Stone. Ranged Weapon Attack: +5 to hit, range 300/1,200 ft. (can't hit targets within 60 feet of it), one target. Hit : 44 (8d10) bludgeoning damage.

A trebuchet is a powerful catapult that throws its payload in a high arc, so it can hit targets behind cover.
Before the trebuchet can be fired, it must be loaded and aimed. It takes two actions to load the weapon, two actions to aim it, and one action to fire it.

A trebuchet typically hurls a heavy stone. However, it can launch other kinds of projectiles, such as barrels of oil or sewage, with different effects.