Heart of the Oak: Weapon Rune Word - Diablo 2
Heart of the Oak is one of the best available Rune Words for almost any caster; it is completely useless to any melee builds. The +3 To All Skills, 40% Faster Cast Rate, Replenish Life, All Resistance, Max Mana Increase among other benefits make this weapon the best universal caster weapon in the game.
Most people choose to put this into a Flail as that will give it the lowest Dex/Str requirement possible. Staves are all 2h which means you won't be able to use a shield with one equipped, which basically means you're just wasting an entire slot.
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: Ko -- Vex -- Pul -- Thul
Level Req: 55
Other Req: N/A
Slots: Staves & Maces
+3 To All Skills
+40% Faster Cast Rate
+75% Damage To Demons
+100 To Attack Rating Against Demons
Adds 3-14 Cold Damage
7% Mana Stolen Per Hit
+10 To Dexterity
Replenish Life +20
Increase Maximum Mana 15%
All Resistances +30-40 (varies)
Level 4 Oak Sage (25 Charges)
Level 14 Raven (60 Charges)