Falling and Landing
Last Grasp
Creatures forced off any ledge may use their Reaction to attempt to catch themselves from falling. Creatures must succeed on a DC 10 Dexterity Saving throw to avoid the fall. If they do succeed they are instead knocked prone. If they fail they fall as normal.
If the creature was pushed particularly hard or far off a ledge then the number of meters they would have been pushed past the edge is added to the DC to avoid falling.
Fall Speed
Creatures in free fall immediately drop at a rate of 10-30 meters per Round(conscious or unrestrained creatures can slow their descent with Motions and Reactions).
Each round that a creature is conscious during free fall they may use a Reaction or Motion to slow their descent(down to 10 meters per Round) and they may use their their Movement or Action(via the Sprint Action) to adjust the sideways movement of their fall by up to 2 meters.
Fall Damage
Creatures receive damage at the end of any fall of more than 3 meters. The damage from falling and suddenly stopping at the bottom is equal to 1d10 Blunt Damage per meter(over 3) dropped. Creatures landing from a fall can use a Reaction or Motion to Roll a Dexterity Saving Throw to attempt reduce the number of damage dice rolled by a number equal to their Dexterity or Constitution modifier. Saving Throw DC = 10 + 1 per every 5 meters of fall distance.