Ōdzutsu are martial, ranged weapons made to essentially be a portable cannon that shoot off blunt cannonballs that deal 2d10 bludgeoning damage on a hit and have the Ammunition, Loud, Two-Handed and Special properties. They have a normal range of 150 feet and a long range of 600 feet.

Properties

Ammunition
You can use a weapon that has the ammunition property to make a ranged attack only if you have ammunition to fire from the weapon. Each time you attack with the weapon, you expend one piece of ammunition. Drawing the ammunition from a quiver, case, or other container is part of the attack (you need a free hand to load a one-handed weapon). At the end of the battle, you can recover half your expended ammunition by taking a minute to search the battlefield. If you use a weapon that has the ammunition property to make a melee attack, you treat the weapon as an improvised weapon.

Loud
The sound of the weapon discharging alerts all hearing creatures within 500 feet. This range is doubled in echoey locations, such as cave systems, and where sound travels faster, such as underwater.

Two-Handed
This weapon requires two hands when you attack with it.

Special: Long Reload
After an attack is made using this weapon, it must be reloaded. Due to the weight and size of this weapon and its ammunition, reloading the weapon takes two actions, which don’t need to be taken consecutively.

Superior Strike

Piercing Shot.
You fire a shot from your weapon packed with destructive force. It flies in a straight line a number of feet up to your weapon’s normal range. Each creature whose space the ammunition passes through must make a Dexterity saving throw. A creature takes piercing damage equalling a number of d6s equal to your proficiency bonus on a failure, or half as much damage on a success. The shot stops early after it passes through the space of a Huge or larger creature, or through an object more than 1 foot thick or with an AC of 17 or higher.