# Bulwark

For the Dungeoneering boss, see Bulwark beast.
 This article has a calculator here.Calculators determine experience and costs based on real-time prices from the Grand Exchange Market Watch.

Bulwark is an Invention perk that lengthens the duration of Debilitate but decreases all damage it deals to 0. It can be created in armour gizmos.

Bulwark's extra duration seems to be a minimum of +1 game tick per rank. The only combinations of shield tiers and Bulwark ranks where the increase in duration is larger than +1 per rank are tier 80 with Bulwark 4 and tier 90 with Bulwark 3 or 4. This does then mean that using Debilitate without a shield will still see an increase in duration from the Bulwark perk for all ranks.

Bulwark 3 increases Debilitate's uptime by 2.4 seconds out of 30 if used with a tier 90 shield. This is a 17.3% increase, resulting in 8.65% overall increased damage reduction provided the player uses the ability every 30 seconds when it comes off cooldown, has 100% hit chance, is fighting against one opponent, and damage taken is not classified as hard typeless.

 template  = Calculator:Template/Combat/Bulwark
form      = bulwarkCalcForm
result    = bulwarkCalcResult
param     = shieldTier|Shield Tier|90|int|0-99


This text will disappear if the form is loaded properly.
This text will disappear if the form is submitted.
• The same calculator along with documentation can be found at the top of this page.
Calculations
Notes
• ${\displaystyle R}$ is the rank of the Bulwark perk.
• ${\displaystyle t}$ is the length of time, measured in game ticks, that Debilitate would last if the Bulwark perk were not used. This value does include the tier of shield being used.

• The length of time (in game ticks) that Debilitate lasts with the Bulwark perk, ${\displaystyle t_{B}}$, is
${\displaystyle t_{B}=t+\max \left(R,\left\lfloor t\times .06\times R\right\rfloor \right)}$
Debilitate length
Rank Increase Time
Minimum[1] Maximum[2]
None 0% 7.8s 13.8s
1 6% 8.4s 14.4s
2 12% 9.0s 15.0s
3 18% 9.6s 16.2s
4 24% 10.2s 16.8s
1. ^ As calculated with no shield equipped
2. ^ As calculated with a tier 90 shield equipped

## Sources

MaterialRarityPerk ranks with X materials
Standard gizmoAncient gizmo
12345123456789
Resilient componentsRare01223011–2222–33–444
Cover partsCommon011–21–21–20111–21–21–21–31–31–4
Powerful componentsUncommon011–21–21–3011–21–21–21–31–41–41–4
Heavy componentsUncommon011–21–21–3011–21–21–21–31–41–41–4
Metallic partsCommon011–21–21–20111–21–21–21–31–31–4

### Suggested gizmos

Gizmo layout Possible perks
Chance increases with and level 120.
• Other possible perks:
Chance increases with and level 120.
• Other possible perks:
• Other possible perks:

## Update history

This information has been compiled as part of the update history project. Some updates may not be included - see here for how to help out!
• patch 18 July 2016 (Update):
• The Bulwark perk now scales correctly.