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Barricade is an ultimate Defence ability that requires a shield to activate. For up to 10 seconds, the user is immune to all damage, including all typeless damage (both soft and hard), unless the player receives an attack that disables defensive abilities. It does not prevent stuns, but the damage associated with the stunning attacks is negated.

The amount of time Barricade is active scales with the tier of the shield or defender equipped; this duration varies from 4.8 seconds (8 game ticks) with the use of a tier 1 shield and 10.2 seconds (17 game ticks) with the use of a tier 90 shield. It seems to be that for every 10 tiers of shield, one extra tick is added to the duration.

Calculations
• The length of time (in game ticks) that Barricade lasts (only taking the tier of shield used into consideration), ${\displaystyle t_{\text{Barricade}}}$, is
${\displaystyle t_{\text{Barricade}}=8+\left\lfloor {\frac {T_{\text{shield}}}{10}}\right\rfloor }$
Notes
• ${\displaystyle T_{\text{shield}}}$ is the tier of the shield used.

If activated with a defender, the defender's tier in regard to calculating Barricade's duration is halved. For example, the Kalphite defender is a tier 90 defender but acts like a tier 45 shield and it is the tier 45 that is used to determine the length of Barricade's duration.

If the shield or defender is unequipped or switched to a different shield or defender while Barricade is still active, the ability immediately ends.

The Turtling perk extends the duration of this ability in exchange increasing its cooldown.
The Malletops perk can also extend the duration of this ability (without affecting the cooldown).

Update history

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• patch 11 March 2019 (Update):
• The following message now gets shown once and then filtered for 10 seconds: "Barricade blocks all damage!"
• patch 8 February 2016 (Update):
• The Barricade ability’s up-time once again displays correctly on the buff bar when active.

Trivia

• Prior to 16 May 2016, Barricade had a static timer of 10 seconds regardless of the tier of the shield used. It also used to be able to block all damage from Heal Other or Heal Group allow players to give other players free heals at the cost of 100% adrenaline.
• Due to player feedback after this change, Jagex eventually reverted this change, simply adding a cooldown timer on Heal Other/Group instead.