Knockback (5e Variant Rule)
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It is in keeping with many genres for mighty blows to knock characters down or even send them flying across the battlefield. The following rules allow this to happen in your games, changing the dynamic of combat appropriately.
|Titanic||+60 or more|
For Example: A commoner has a Strength of 10, a Constitution of 10, and is Medium size. Thus, a commoner's mass would be (10+10)/2, or 10, +0. On the other hand, a frost giant has a Strength of 23, a Constitution of 21, and is Huge size. Thus, a frost giant's mass would be (23+21)/2, or 22, plus 10 for size, for a total of 32.
Damage Reduction and Knockback
DR does not reduce damage for the purposes of knockback, unless the source of DR is natural, or otherwise innate to the creature.
When a creature take's damage equal to or greater than its mass, it is knocked back 5 feet for every 5 points of damage it took above its mass, with a minimum of 5 feet. If a knocked back creature strikes an object, such as a wall or floor, both the creature and the object take 3 (1d6) bludgeoning damage for every 10 full feet it was knocked back. If a creature is knocked back into another creature, that creature must succeed on a Dexterity saving throw or take the same damage and be knocked prone. The DC of the Dexterity saving throw is the same as the DC of the Acrobatics check described below.
A creature which is knocked back can make an Acrobatics check to remain on its feet. On a failure, it is knocked prone. The DC of the acrobatics check depends on the distance the creature is knocked back, as shown on the table below.
|KB Distance||Acrobatics DC|
|10 feet or less||10|
|75 feet+||Impossible! Automatic failure.|
Fluid Creatures, Incorporeal Creatures, and Swarms
Special considerations have to be made for diffuse creatures that reasonably do not react to blows the same way solid creatures do. A creature belonging to one or more of those categories is more likely to be blown apart or scattered than pushed back. Assume that knockback does not apply, except as the result of an area effect attack such as a cone, line, or burst which completely covers such a creature's space.
Damage Which Does not Cause Knockback
Special considerations also have to be made for certain attacks and damage types which cannot justifiably cause knockback. For example, a purely mental psionic mind blast can't cause knockback, and neither can poison in most instances.