Oath: Weapon Rune Word - Diablo 2
Oath is one of the best available mid level Rune Words due to the fact that you can Socket it into an Ethereal item greatly improving the damage done by the weapon. Since Oath makes the weapon Indestructible it means the only thing you have to worry about with an Ethereal weapon (it breaking) is no longer a problem. This Rune Word is generally used by people on a budget that can't or don't want to invest in the more expensive weapon Rune Words like Breath of the Dying or Eternity.
As you can probably tell based on the stats, Oath is a Rune Word that is designed for melee fighters. It has some of the highest +Enhanced Damage possible on a weapon with the obvious downside being it can roll anywhere from 210 - 340% (a pretty big gap).
Keep in mind that all Rune Words you create will retain any pre-existing bonuses found on the item. If you find a 'Superior' piece of armor with +Enhanced Defense, a Superior Weapon with +Enhanced Damage or a Helm/Weapon that has +Skill bonuses for a certain class, all of these will remain on the final Rune Word that is created. It's also possible to 'ebug' a piece of Ethereal Armor that you find which will increase the Defense bonuses by 50%, check out my Ebugging Guide for more information.
Farming High Runes: Out of all locations in the game one stands above the rest for farming specifically High Runes, the Countess during Act 1. The Countess has a guaranteed chance to always drop a High Rune and can even drop more than one. Check out my The Countess Farming Guide for more information.
Required Runes: Shael -- Pul -- Mal -- Lum
Level Req: 49
Other Req: Ladder Only
Slots: Axes, Maces and Swords
30% Chance To Cast Level 20 Bone Spirit On Striking
+50% Increased Attack Speed
+210-340% Enhanced Damage (varies)
+75% Damage To Demons
+100 To Attack Rating Against Demons
Prevent Monster Heal
+10 To Energy
+10-15 Magic Absorb (varies)
Level 16 Heart of Wolverine (20 Charges)
Level 17 Iron Golem (14 Charges)