Do you go to the dungeon?

Climbing

A lot of this is from Veins of the Earth, fantastic book♥

Route Types

Abseiling Climb

Rope (already fastened up there) & Peace & Quiet

No roll needed.

Fighting or Distraction

Strength (study for DC).

Level three thief Second Story Work gets expertise on their strength roll at this route, if they don't already have expertise in strength.

Level nine monk Unarmored Movement can run here without if they are unencumbered but when their movement ends they need to roll to grab hold, or be on solid ground.

No rope?

Counts as Hard Climb, see below.

Sloping Climb

Peace & Quiet

No roll needed.

Fighting or Distraction

Strength (study for DC).

Level three thief Second Story Work gets expertise on their strength roll at this route, if they don't already have expertise in strength.

Level nine monk Unarmored Movement can run here without if they are unencumbered but when their movement ends they need to roll to grab hold, or be on solid ground.

Hard Climb

Encumbered

No chance.

Rope (already fastened up there) & Peace & Quiet & Unencumbered

No roll needed.

Fighting, Distraction or lack of Rope

Strength (study for DC).

Level three thief Second Story Work gets expertise on their strength roll at this route, if they don't already have expertise in strength.

Level nine monk Unarmored Movement can run here without if they are unencumbered but when their movement ends they need to roll to grab hold, or be on solid ground.

Tip! If you make it, set a rope for your friends with hammers, pitons etc.

Very Hard Climb

Encumbered

No chance.

Unencumbered

Strength (study for DC).

Level three thief Second Story Work gets expertise on their strength roll at this route, if they don't already have expertise in strength.

Human Limit Climb

Encumbered or no Second Story Work

No chance.

Unencumbered & Second Story Work

Strength (study for DC).

Superhuman Climb

Encumbered or no Second Story Work

No chance.

Unencumbered & Second Story Work

Strength (study for DC).

Climbing on a Giant or other monster

No route studying needed.

For the initial climb, "strexterity" vs their dexterity. (They are trying to shake you off.) One you're up there, "strexterity" vs their strength to stay on there. (They are trying to scrape you off or knock you off.)

Vice versa when tiny creatures climb on you.

Studying

Unencumbered

No studying: DC 20
10 minutes studying: DC 10

Encumbered

Encumbered adds 5 to DC. Heavy encumbered instead adds 10 to DC. This is only for abseiling or sloped climbs, harder climbs you can't succeed if you're encumbered.

DC capped routes

Some routes have a minimum DC that you can't go under.

These come from modules (Tomb of A have some routes like this), never from the natural veins.

Spider Climb spell, or monster with Climbing speed

Don't worry you can easily traverse any of these w/o rolling, except climbing on a Giant or other monster.