Houserules

Damage types have been reworked.

Sorcerers have been modified.

Small creatures jump higher.

Smaller creatures take less fall damage. Larger creatures take more fall damage.

Jumping
Your Strength determines how far you can jump.

Long Jump
When you make a long jump, you cover a number of feet up to your Strength score if you move at least 10 feet on foot immediately before the jump. When you make a standing long jump, you can leap only half that distance. Either way, each foot you clear on the jump costs a foot of movement.

This rule assumes that the height of your jump doesn't matter, such as a jump across a stream or chasm. At your DM's option, you must succeed on a DC 10 Strength (Athletics) check to clear a low obstacle (no taller than a quarter of the jump's distance), such as a hedge or low wall. Otherwise, you hit it.

When you land in difficult terrain, you must succeed on a DC 10 Dexterity (Acrobatics) check to land on your feet. Otherwise, you land prone.

High Jump
When you make a high jump, you leap into the air a number of feet equal to 3 + your Strength modifier (minimum of 1 foot) if you move at least 10 feet on foot immediately before the jump. When you make a standing high jump, you can jump only half that distance. Either way, each foot you clear on the jump costs a foot of movement. In some circumstances, your DM might allow you to make a Strength (Athletics) check to jump higher than you normally can.

You can extend your arms half your height above yourself during the jump. Thus, you can reach above you a distance equal to the height of the jump plus 1½ times your height.

Smaller Creatures
Small creatures may be diminutive, but they have a much higher strength-to-weight ratio than their larger counterparts, allowing them to lift their own bodies with greater ease. A Small or Tiny creature can add 3 feet to the height of their long or high jumps in addition to the normal calculation.

Falling
Falling from a great height is a significant risk for adventurers and their foes. At the end of a fall, a creature takes a number of bludgeoning damage for every 10 feet you fell, to a maximum of 500 feet. You also land prone, unless you somehow avoid taking damage from the fall. The damage a creature takes per 10 feet varies depending on their size.

Rate of Falling
The rule for falling assumes that a creature immediately drops the entire distance when it falls. But what if a creature is at a high altitude when it falls, perhaps on the back of a griffon or on board an airship? Realistically, a fall from such a height can take more than a few seconds, extending past the end of the turn when the fall occurred. If you'd like high-altitude falls to be properly time-consuming, use the following optional rule.

When you fall from a great height, you instantly descend up to 500 feet. If you're still falling on your next turn, you descend up to 500 feet at the end of that turn. This process continues until the fall ends, either because you hit the ground or the fall is otherwise halted.

Flying Creatures and Falling
A flying creature in flight falls if it is knocked prone, if its speed is reduced to 0 feet, or if it otherwise loses the ability to move, unless it can hover or it is being held aloft by magic, such as the fly spell.

If you'd like a flying creature to have a better chance of surviving a fall than a non-flying creature does, use this rule: subtract the creature's current flying speed from the distance it fell before calculating falling damage. This rule is helpful to a flier that is knocked prone but is still conscious and has a current flying speed that is greater than 0 feet. The rule is designed to simulate the creature flapping its wings furiously or taking similar measures to slow the velocity of its fall.

If you use the rule for rate of falling in the previous section, a flying creature descends 500 feet on the turn when it falls, just as other creatures do. But if that creature starts any of its later turns still falling and is prone, it can halt the fall on its turn by spending half its flying speed to counter the prone condition (as if it were standing up in midair).