Strength represents your ability to use your muscles! Some situations require brute force like kicking in a door or lifting a large box full of treasure. It especially comes in handy when you need to rely on your Athletic abilities to swim or climb!
A character with a high Strength score is in great physical condition and is capable of nearly herculean feats of strength. Whether they’re helping carry a heavy load or swinging a battle axe like there’s no tomorrow, none can deny these characters’ physical prowess!
A character with a low Strength score may have difficulty with these skills. The studious Wizard spends so much time reading in the library that they rarely need to lift anything heavier than a book. Perhaps the charismatic Bard is a gifted performer but lives a relatively sheltered life. There are plenty of servants to take care of the heavy lifting at their family’s estate!