A few more rules clarifications/crunch and miscellaneous rules. Classic and OSR games.

A companion to this post. 

Climbing 
Disguises
Interrogation
Languages 
Swimming
Torture
Scars

Climbing 
In most classic base rules only a those classes with the thief ability of climb walls can scale sheer surfaces such as cliffs with minute handholds, brick walls, etc.

For more normal climbs checks I use a simple Str check with the following modifiers:

Climbing aide (rope, harness, ladder, rope ladder). 4 bonus
Chain fence, good hand holds. No bonus or penalty to roll.
Few hand holds. 2 penalty
Slippery. 4 penalty
Brace in corner. 2 bonus
Brace between two surfaces. 4 bonus

Disguises
Anyone can pass off a  general disguise if they are not impersonating someone else's identity and are not the subject of intense fame, a manhunt, etc.

Charisma check required for a suspicious audience.
Showing up as a simple farmer with sword scars on wrists and face might arouse suspicion, a Halfling disguised as a small child, etc.

IF they are famous or are trying to disguise as a specific person the following modifiers apply:
Never seen by the audience, No roll
*Seen in papers, tv, has some knowledge of subject. No bonus or penalty to roll.
*Seen briefly in person, passing acquaintance. 4 penalty
*Friend, associate, well known. 8 penalty
Audience drunk, drugged, impaired. 4 bonus
Dim Lighting. 4 bonus

* Requires a disguise of some sort.

Interrogation
The subject of intense interrogation must make one Saving Throw (Paralysis) per hour of interrogation. Any Wisdom bonus is applied to the Saving Throw. Other modifiers include:
Penalty equal to  Interrogators Int bonus.
1 penalty per four hours without rest, food, etc.
4 penalty if drugged.

If allowed to rest, start over.

Number of Languages
Up to Int 10 = one language. +1 language per point of Int past 10.

Scars
After combat total dmg taken. Roll this number or less on percentiles take a 1d3 Cha penalty for a VISIBLE scar on the head or face.

Scar location 1d20:
Head 1-3
Neck 4-6
Chest 7-9
Back 10-12
R. Hand 13
L. Hand 14
R. Arm 15-16
L. Arm 17-18
R. Leg 19
L. Leg 20

Swim
Move: Half normal move if nothing but swimming. 1/4 if any other activity.
Hold breath: 1 round (10 seconds) per two point of Con.
Attack: Thrust attacks, grapples  are at 0 penalty to hit. Punch, swing, chop, etc -4 hit.
Visibility:  Clear 0 penalty. Murky/cloudy -2 hit. Inky -4 hit.

SCUBA Gear
Full normal move with flippers.
Air Tanks: half hour per tank (limit two) in 1980's and earlier. One hour per tank modern.
Speargun: 1d6 dmg, 20' inc., 1 shot per round.
Bangstick: 3d6, touch, 1 shot.

Torture
The subject of torture takes 1d2 dmg per turn.
The subject must make one Saving Throw (Paralysis) per per turn (10 minutes). The subjects constitution bonus to the Saving Throw. The following modifiers also apply:
1 penalty per point of dmg taken.
1 penalty four hours without rest, food, etc.
1 penalty four hours without rest, food, etc.
4 1 penalty if drugged.

If allowed to rest, start over.