Doublestrike / Doublestike

Doublestrike gives you a percentage change to take an additional attack with your main hand melee weapon. If you have a 6% double strike then you will get a bonus attack roughly 6 out of 100 attacks. It does not impact ranged attacks, spells, off hand attacks, or attacks using special animations (like cleave, trip etc…) It will affect special attacks using standard animations such as smites or ki strikes.

The number of sources of doublestrike is small compared to many other bonuses you can get, but there are still quite a number of them in the game. Stacking rules for doublestrike have never been entirely verified by devs. It seems that differently typed double strike bonuses will stack and same type bonuses will not. Untyped bonuses only stack if they are from a different source, aka a weapon will stack with a feat will stack with an enhancement, but two feat bonuses without types will not stack. If they do not stack then you should get the largest bonus.

You can see your current double strike bonus by hovering over the BAB icon (its red) in the character sheet Stats page.

Types of Doublestrike in DDO

So lets go over the different sources of double strike and group them by what should not stack and order them from largest to smallest

Mystery Shield Bonus - An untyped 4% for using a shield

Competence Bonuses - Fighter Weapon Alacrity capstone (fighter 20) 10%

Sacred Bonuses - Paladin Zeal spell (level 14 pally) 10% (no scrolls, self only, temporary)

Insight Bonus - Monk Windstance  2.5%/5%/7.5%/10% levels 1/6/12/18 respectively

Morale Bonus

• Shield Mastery / Improved Shield mastery  3%/8% when using a shield
• Timeblade (longsword) 3%  /  Epic Timeblade 6%
• Hellstroke Great Axe 3% / Epic 6%
• Cutthroat’s Smallblade (shortsword) 3% / 6% with tier 3 upgrades
• Swashbuckler (shield)  3% / 6% with tier 3
• Alchemical Weapon (any) Teir 2 Martial Air 6%
• Antipode, Fist of the Horizon (handwraps) 6%
• Bard Warchanter 2 Inspire Recklessness song 5% (level 12)
• Way of the Sun soul set bonus effect +6% (temporary)
• Epic Spare hand (belt) 3%

Untyped type Class Feats/Enhancements

• Natural Fighting 6%  (druid level 9) can be taken up to 3 times for 18% total
• Ranger Tempest 3  (level 18)  5% when wielding two weapons
• Rogue Opportunist feat  3%  (level 10)

Alchemical Bonus

• Fabricator’s Bracers with Combat Infusion 5% (temporary)

Untyped epic Destinies  (seem to stack with non epic sources)

• Sentinel : Legendary Shield Mastery 6% when using a shield
• Legendary Dreadnaught: Lightning Mace 15% bonus after Vorpal strike for 6 seconds
• Grandmaster of Flowers: Hail of Blows 3%
• Grandmaster of Flowers: running with the Wind 3% (in wind stance)

Profane Bonus

• Shadowdancer: ShadowTraining 4 3% (certain light weapons only, temporary)

So who can have the most double strike?

Druids are king of full time double strike, but shield base builds, monks and two-weapon fighters are in the top ranking for doublestrke efficiency.
Shield based

• +18 if you take three levels of natural fighting: 18%
• If you use a shield you can get +8 from shield mastery (another two feats) and the +4 base shield bonus giving you 30%
• Legendary shield mastery stacks for another 6% taking you to 36%
• +3 Twist Hail of Blows for
• 39%

Monk Multiclass

• +18 for natural fighting
• +5 for second tier wind stance
• +3 from Hail of blows, and +3 from Running with the Wind
• +6 from an item for
• 35%

Each could squeeze in temporary bonuses from Shadowndancer and Combat infusion for a short term max of 47% though it would be quite unreliable to get it and only last seconds.

After the druids you would have shield using fighters and paladins, then non druid wind monks.

Anything you can do that bumps attack speed will also enhance double strike. Monk unarmed and Druid wolf forms both have faster than usual attack animations, Rogues and Fighters can get combat speed boost enhancements (also available in the dreadnaught line).

Ultimate double strike build?  Probably a half orc Druid with a splash of rogue and or fighter wielding a shield in wolf form.

Thanks to the DDOWiki and SteeleTrueHeart for their hard work in collecting and testing information about Doublestrike!