Heavy Cannon (5e Equipment)
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Martial Ranged Weapons
One of the oldest types of firearms, the heavy cannon is a large brass barrel with a blast chamber to internalize the explosive force required to ignite a light cannonball. Similar to the hand cannon, it requires direct manual external ignition through a touch hole without any form of firing mechanism. However, while it packs a much larger payload than an ordinary handheld firearm, its sheer weight makes it quite unwieldy to all but the strongest of users.
This weapon uses small cannonballs as ammunition.
Add both your strength and your proficiency bonus to the damage roll upon impact with a target creature.
When the target creature is hit, it must make a Strength(Athletics) saving roll with a DC of (7 + your proficiency bonus). On a failed roll, the target creature is:
The sheer force of the weapon and its massive backblast makes it awkward to fire. Every time the heavy cannon is fired, make a Strength(Athletics) check with a DC of (13 - your Strength modifier). On a failed save, your character is knocked prone after firing.