Divine spirit shield

The Divine spirit shield was released on 15 September 2008 along with Summer's End. It requires 75 Defence and 75 Prayer to wield. Players with 90 Prayer and 85 Smithing can attach a Divine sigil to a Blessed spirit shield to make a Divine spirit shield, granting 1800 Smithing experience. Alternately, you can ask Brother Bordiss to attach it for 1,500,000 coins after completing Perils of Ice Mountain.

Special Bonus
The Divine spirit shield comes with a special bonus that reduces 30% of any damage a player takes if the player has sufficient Prayer points. 5% of this 30% is deducted from the player's Prayer, while the rest is ignored. The formula for the reduced damage is: $$Damage Received * 0.7$$ and the formula for Prayer drain is $$Ceiling((Damage Received * 0.3) / 20)$$.

For example, if an opponent were to hit 500 LP of damage on a player wearing this shield, the damage would be reduced to 350 (since $$500 * 0.7 = 350$$), and the player would lose 8 Prayer points (since $$Ceiling(150 / 20) = 8)$$. The damage reduced by this shield is therefore limited to 20 times one's current Prayer points, e.g. a player with 75 Prayer points can have 1500 Life points of damage reduced from any attacks.

This shield stacks with Protection Prayers multiplicatively, not additively. The prayer drain and damage reduction act before Protection Prayers. For example: when fighting against a player, the shield reduces damage by 30% and then a protection prayer reduces the remaining damage by 40%. In this way, exactly 58% of the damage taken is protected from, and 1.5% of the original damage is reduced from the defending player's Prayer points.

This shield has the exact same defence bonuses as the Elysian spirit shield; however, their special effects differ slightly. While the Elysian spirit shield has a 70% chance of reducing damage by 25%, this shield will ALWAYS reduce any incoming damage by 30%, assuming the player has sufficient Prayer points. This means that an average of 17.5% of all damage received while wearing the Elysian spirit shield is negated, whereas 30% of all damage from the Divine spirit shield is negated and 1.5% is deducted from the player's Prayer points. In this aspect, the Divine spirit shield is the more powerful shield, yet nonetheless, it is more tedious to use. The price to pay for its constant reduction of damage is the loss of Prayer points, which can be expensive. However, the cost of restoring the Life points saved often make up for the Prayer potions or Super restore potions used, especially in PvP situations.

When comparing the two bonuses it shows that, assuming the Elysian spirit shield special bonus reduces the damage on average by 17.5% it is cheaper in use than the Divine spirit shield when using normal prayer potions to regain lost prayer points even at level 99 prayer. This calculation was made based on prayer potions costing 6573gp for a 4 dose prayer potion. And sharks were used to calculate the amount of money saved in the first place. These calculations however are only theoretical since you cannot rely on the Elysian spirit shield always reducing damage at the right times and keeping it equal. For this reason, an Elysian spirit shield is preferable for low-risk combat situations (such as general training), while the Divine is better for high-risk situations.

As 5% of the unreduced damage is drained from prayer, assuming no prayer use, the shield has the potential to absorb 1500 damage at the minimum prayer level of 75. This means that a player at 99 constitution, and with 99 prayer, could have the equivalent of 2970 hitpoints.

A good method of restoring prayer while using this shield is using a Bonecrusher together with the Twisted bird skull necklace, Split dragontooth necklace or Demon horn necklace to regain prayer points.

Trivia

 * On 1 February 2010, the spirit shields' appearances were changed to match their inventory pictures. The Divine spirit shield's colour was changed to a more vibrant green. Previously the Arcane spirit shield and Divine spirit shield were close to the same pale shade of green.
 * The Divine spirit shield was the first non-discontinued item to reach a Grand Exchange price of higher than 1 billion coins.