Elden Ring’s String material certainly screams “sell” just by looking at it, but we can confidently say that it is worth holding onto. The item is the only difference between crafting pots and roped bots, and this distinction is crucial to know of when fighting herds of enemies. Unfortunately, String is very limited in the game, but the enemy you can nab it from is one of the easiest you will be fighting.
Although String can be found on corpses throughout the map, it is mainly collected from pillaging Demi-Humans, the goblin-like enemies usually armed with clubs. You can fight a handful of Demi-Humans just north of Limgrave’s Coastal Cave or under the bridge that is north of Mistwood Ruins (as marked below). The crafting material is not guaranteed to drop from this creature after each fight, but you’re bound to obtain at least one String after defeating three or four.
String is exclusively used to craft elemental roped pots, including Roped Fire Pots, Roped Holy Water Pots, Roped Poison Pots, and Roped Fetid Pots. As regular pots can only be thrown forward, roped pots can be dropped from behind you. Thus, these make for excellent tools when fighting herds or enemies that tend to chase you endlessly.