Each foot of movement costs 1 extra foot (2 extra feet in difficult terrain) when you’re climbing or crawling. You ignore this extra cost if you have a climbing speed and use it to climb. At the DM’s option, climbing a slippery vertical surface or one with few handholds requires a successful Strength (Athletics) check.
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 0 feet) 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 1 1/2 times your height.
FALLING
A fall from a great height is one of the most common hazards facing an adventurer.
At the end of a fall, a creature takes 1d6 bludgeoning damage for every 10 feet it fell, to a maximum of 20d6. The creature lands prone, unless it avoids taking damage from the fall.
Falling or Jumping into Water
When jumping into water or another liquid the damage is instead:
No damage for 20 feet of falling.
Half-damage next 20 feet.
Normal damage beyond that.
A creature that falls into water or another liquid can use its reaction to make a DC 15 Strength (Athletics) or Dexterity (Acrobatics) check to hit the surface head or feet first. On a successful check, any damage resulting from the fall is halved.
