This massive crossbow has a modified firing mechanism which makes it challenging to use but capable of firing extremely long distances. If you take an action to set it up the range of this crossbow becomes 250/1000 but it must be set up again if you move. This crossbow has 3 charges and it regains all expended charges each day at dawn.
If you currently know the location of a creature due to the effect of divination magic making an attack at long range against that creature no longer imposes disadvantage. Additionally, attacks against that creature ignore half cover and three-quarters cover.
As an action you can activate the crossbow, expending a charge. When you do so you can target any point you can see, or divine, within range. A streak of brilliant purple light screams from the mouth of the crossbow towards the target. Roll 1d4-1 and move the point where the bolt strikes that many squares in a random direction from the targetted location. Any creatures within 20 feet of that point must make a DC 16 Constitution saving throw as the bolt lands with an immense boom. On a failure they take 5d6 Thunder damage and are Deafened for 1 minute. On a success they take half as much damage and are not Deafened.