Size
Creatures larger or smaller than 5 get the following adjustments listed below.
SIZES
Every creature and object has a size, most scaling from 1 to 10 (though larger and smaller things are possible). Most adult humans and other playable origins are size 5 (aka "medium-sized") standing more than 1 meter/yard tall but less than 3 meters/yards tall. They occupy roughly a 2 x 2 x 2 meter/yard cube of space and can reach everything within their space or within their reach. Every size lower is roughly half as big while every size larger is roughly 50% bigger than the previous size. (Size2)/5 = space in feet (space x space x space).
SIZE 6
+1 size bonus to...
-1 size penalty to...
*For each size larger, you stack these adjustments. So it would be +4/-4 for Size 7 (Huge), +6/-6 for Size 8 (Gargantuan), +8/-8 for Size 9 (Colossal), etc.
SIZE 4 (SMALL)
+1 size bonus to...
-1 size penalty to...
*For each size smaller, you stack these adjustments. So it would be +4/-4 for Size 3 (Tiny), +6/-6 for Size 2 (Diminutive), +8/-8 for Size 1 (Fine), etc.
ACTIONS
If a creature is two sizes larger or smaller than you, you...
- cannot flank them
- cannot gain high ground bonuses against them
- cannot take attacks of opportunity against them
- can move through their space without having to overrun them, treating it as difficult terrain*
Creatures with the Blobular shape or Amorphous ability are an exception. They can make attacks of opportunity against creatures of any size smaller and prevent smaller creatures from moving through their space.
*If the creature is 2 sizes smaller than you or smaller, doing this imposes a trampling hazard on the creature (Reflex DC10 + your Brawn modifier or they take damage as if struck by your unarmed strike or slam attack, whichever is worse). If you move normally, they have advantage on this save. If you intentionally try to trample them, they don't have advantage but you move at half speed.
CARRYING CAPACITY
A bipedal creature can carry less or more weight depending on its size category: Fine x1/16, Diminutive x1/8, Tiny x1/4, Small x1/2, Medium x1, Large x2, Huge x4, Gargantuan x8, Colossal x16.
Quadrupeds: Fine x3/32, Diminutive x3/16, Tiny x3/8, Small x3/4, Medium x1.5, Large x3, Huge x6, Gargantuan x12, Colossal x24.
RAGDOLLING
If you pin a creature that is more than 1 size smaller than you, you can use them as an improvised melee or thrown weapon. The damage dealt is based on the victim's size as an object and the wielder's Strength modifier. The victim and the target share the damage dealt 50/50. A grappled creature or swallowed creature cannot suffer this humiliation, only one that remains pinned.
CLIMBING CREATURES
It’s possible to climb a creature that's two sizes larger than you or larger treating their Str DC as the Athletics DC to climb them. If successful, you add your weight to the creature's carrying load and move upwards the appropriate distance. While climbing a creature, you are treated as flanking it for the purposes of weapon attacks you make against it despite the size difference.
MASSIVE
If a creature is more than 4 sizes larger than you, you treat it as terrain rather than an actual creature and can interact with portions of it up to 4 sizes larger. They are immune to damage dealt by weapons that are not area of effects. Siege weapons and massive spells are needed to even scratch such behemoths. For simplicity's sake, treat creatures with this trait as if they were one size larger than colossal.
TARGET CREATURES
Spells and other effects that target 2 or more limited number of creatures or objects are assumed to target medium-sized ones unless noted otherwise. If the spell lifts, moves, grants or adjusts base speeds, or transports targets, assume it can include 4 small targets instead of one medium target, 16 tiny per medium, 64 diminutive per medium, and 256 fine per medium. In reverse it can affect 1 large target per 4 medium targets, 1 huge per 16 medium, 1 gargantuan per 64 medium, and 1 colossal per 256 medium. Effects that target "self", "personal", or only 1 creature, have no size limitation. Instead of targeting objects, you can target a single 5-foot space per medium target and affect a wall, ceiling, or floor (if possible).
WEAPON SIZES
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