Strength is the ability of your muscle(s) to contract and produce force. The ability score includes overall body strength as well as the ability to apply it over a range of circumstances (mobility and stability).
Strength plays a role in melee combat as well as lifting, moving, or opening things. It is particularly important when considering encumbrance—the amount of weight you can carry before being negatively impacted. Characters wearing bulky armor and carrying heavy adventuring gear can use all of the Strength they can get!
Man-sized humanoid creatures can lift 10 lbs. per point of Strength over their head (or almost triple this in a dead lift type of scenario). Small humanoids can lift 70% of this amount. However, in all cases that involve lifting and actually moving, including dragging or pulling things, refer to Equipment, Encumbrance.
Melee Attack and Damage Adjustments. These adjustments are used when the creature attacks with a typical-sized melee weapon in hand to hand combat. These adjustments do not modify natural weapon attacks or missile attacks (unless a special attribute is possessed).
Minor and Major Checks. Sometimes Strength is called upon to break or open things. Minor checks are used for opening stuck doors or containers. Numbers in parenthesis indicate the chance to open a locked portal or container. Opening a container typically requires the aid of a lever (crowbar). Major checks include the ability to break down (barred) doors or to lift a heavy gate or portcullis. These checks can be used, per the GM, for other feats of Strength.
Most man-sized or smaller humanoids will have a Strength ability score rated along a scale from 3 to 18. However, characters that are fighters, rangers, or paladins can possess “Exceptional Strength” which is rated on top of 18 and recorded as a percentile value from 18/01 to 18/00. Limitations will be by race. Some especially strong or large creatures may be rated on the same scale or higher.
Overhead Lift or Dead Lift for Those with Exceptional Strength. A man-sized humanoid with Exceptional Strength is able to lift ("military press") 180 lbs. over it’s head—plus 1 additional pound for every percentage point up to and including 50%, 4 pounds for every percentage point from 51% to 90%, and 8 pounds for each percentage point from 91% to 00%. Dead lifts are triple this number. The GM may adjust both lift types for body weight.
Legendary Strength. Certain huge or otherwise super-strong creatures cannot be rated on the standard scale. These are rated on a scale up to 25. Typically, the scale is referred to as “Giant Strength”, noting the type of giant, as typical giants fall along this scale. While not impossible, it is rare for normal humanoids of man-sized or smaller to possess a Strength of over 18/00 and PCs or NPCs would require magic to do so.
For Strength effects on encumbrance, see Encumbrance.