Runewords are some of D2R Items the most potent items you can create within Diablo 2: Resurrected, though they do take quite the effort in order to complete. First, you must find the appropriate runes in order to create the runeword, then you'll need to locate the weapon such as a shield or armor which can take the runeword. The item must have the precise number of open sockets for the word to work, and also the runes should be placed into the item that is socketed in the right order. Also, the item has to be plain (white) and magical (blue) or rare (yellow) or unique (gold) along with set (green) items that have the proper amount of sockets won't work for runewords.
To avoid this, you must take extreme care when writing a runeword. Doubleand triple check that the items's proper type -like, for example, the Insight runeword can be created using staves and polearms but not spears. Lastly, arrange the runes in the correct order prior placing them in the item.
There are some intricacies when it comes to weapons and armor types that you should make note of. "Body armor" is only for items used to protect your torso. General "armor" includes shields, boots, gloves, helms, etc. Hammers can't be used when using maces runewords. "Melee weapons" don't include melee weapons, such as bows and crossbows. Orbs, too, aren't considered melee weapons.
When creating runewords, many are made up of different statistics that define how good of a roll you've made. A perfect runeword roll is always worth a lot better than a poorly constructed roll. Also using the finest runeword base (an item that has sockets) should be the most suggested. For example, if you're making a runeword that you can equip on a mercenary, always choose an Ethereal base. Mercenary weaponry and armor doesn't get less durable, so they can benefit from cheap D2R ladder items the benefit of stats gained from the Ethereal property without worrying about it breaking. Every boost in stats is counted in Diablo 2: Resurrected.