# Calculator:Combat/Instability

Jump to navigation Jump to search
 This page is maintained in part by a collaboration with the PvM Encyclopedia Discord server.The wiki has partnered with this server (discussion) to improve the quality of our content. You can join the PvM Encyclopedia server on Discord for more help with this activity.The wiki is not responsible for content on this server. For more information, see RuneScape:Discord Affiliates.
Templates used Calculator:Template/Combat/Instability

### Notes

Many sources contribute to the critical hit chance of an attack for Magic. These include (non-exhaustive list):

• Forced critical hit sources
• Natural critical hit chance of an ability or auto-attack
• These typically take on a range between 5% and 13.5%

If tick 1 is considered to be the tick when the player casts the Instability special attack (50 ticks remain on the bar), then tick 2 is when the initial hit fired from the staff lands on the target (49 ticks remain on the bar). Though it is possible to have a hitsplat land on tick 1, it does not cause an auto-attack to be fired if it crits. Therefore, the first tick possible for a given hit to cause an auto-attack to be fired is tick 2, when there are 49 ticks remaining on the bar.

Furthermore, the time between when the player casts the spell and when the auto-attack lands affects the pace at which auto-attacks are fired from the staff. This in turn sets a maximum number of auto-attacks that can be fired from the staff, given the amount of time left on the buff when the player lands their source hit. The (collapsed) table below shows the time in ticks between the cast and the hit landing on the target.

Combat spell speed
Spell speed - The amount of ticks a Magic auto-attack takes to land after cast
1 tick = Fast, 2 ticks = Slow, 3 ticks = Slowest
Type of auto-attack Lands[note 1] (X ticks after cast)
Cast 1-4 squares away from target[note 2] Cast 5-7 squares away from target[note 2] Cast 8 squares away from target[note 2]
Burst 1 1 2
Barrage
Rush 2 3 3
Blitz
Exsanguinate
Incite Fear
Aurora 2 2 2
Strike
Bolt
Wave
Surge
Divine Storm
Storm of Armadyl
Polypore Strike
Slayer Dart
1. ^ Includes area-of-effect properties of spell.
2. ^ a b c 1 square away is melee distance (often called MD or md).
template = Calculator:Template/Combat/Instability
form      = instabilityCalcForm
result    = instabilityCalcResult

param     = critInit|Source critical hit chance (%)|30|number|0-100,0.01,0.01||The critical hit chance from a single source hit.
param     = critAuto|Auto-attack critical hit chance (%)|30|number|0-100,0.01,0.01||The critical hit chance from the auto-attacks fired from the Instability special attack.
param     = ticks|Time remaining on buff bar (game ticks)|49|int|0-49||The time remaining on the buff bar for the special attack in game ticks when the source hit lands on the target. The buff lasts for 30 seconds (50 game ticks).However, if a hit lands on the cast tick and is a critical hit, it will not cause an auto-attack to be fired. Therefore, the earliest tick that a hit can land is the next tick, when the buff has 49 ticks remaining.This allows for a maximum of 50 recursive auto-attacks for fast magic spells, 25 for slow magic spells, and 17 for slowest magic spells.
param     = speed|Select speed of spell|Slow|buttonselect|Fast,Slow,Slowest||The speed of the spell affects how quickly a recursive auto-attack follows the previous auto-attack. For fast spells, a recursive auto-attack follows 1 game tick after the previous auto-attack. For slow spells, it is 2 game ticks. For slowest spells, it is 3 game ticks.

param     = calculateDamage|Calculate total expected damage|false|toggleswitch|true,false|true=expectedDamage|Toggle parameters for calculating the approximate total expected damage.
param     = expectedDamage|Calculate total expected damage||group|initHitAverage,autoHitAverage
param     = initHitAverage|Source hit average damage|3500|int|0-32767||The expected damage of the source hit.
param     = autoHitAverage|Auto-attack average damage|8000|int|0-32767||The expected damage of an auto-attack.

This text will disappear if the form is loaded properly.
This text will disappear if the form is submitted.
Template documentation
This documentation is transcluded from Calculator:Combat/Instability/doc.  [history] [purge]

### Description

The purpose of this calculator is to calculate the expected number of auto-attacks fired from the Fractured Staff of Armadyl special attack, Instability, given the probability that a source hit will land a critical hit and the probability of the subsequent auto-attacks landing critical hits. In addition, the spell speed of the auto-attacks are taken into consideration, as well as the time of the buff provided by the special attack on the player's buff bar.

There are optional parameters that can be toggled on to calculate the approximate total expected damage for a given source hit average damage and auto-attack average damage.

### Source critical hit chance (%)

The critical hit chance from a single source hit. Values can be between 0-100 in increments of 0.1.

### Auto-attack critical hit chance (%)

The critical hit chance from the auto-attacks fired from the Instability special attack. Values can be between 0-100 in increments of 0.1.

### Time reamining on the buff bar (game ticks)

The time remaining on the buff bar for the special attack in game ticks when the initial hit lands on the target. The buff lasts for 30 seconds (50 game ticks). However, if a hit lands on the cast tick and is a critical hit, it will not cause an auto-attack to be fired. Therefore, the earliest tick that a hit can land is the next tick, when the buff has 49 ticks remaining. This allows for a maximum of 50 recursive auto-attacks for fast magic spells, 25 for slow magic spells, and 17 for slowest magic spells.

### Select speed of spell

The speed of the spell affects how quickly a recursive auto-attack follows the previous auto-attack. For fast spells, a recursive auto-attack follows 1 game tick after the previous auto-attack. For slow spells, it is 2 game ticks. For slowest spells, it is 3 game ticks.

### Calculate total expected damage

Toggles the display for optional parameters used for calculating an approximated total damage from the source hit and auto-attack damages. The approximation is ${\displaystyle {\text{E}}={\text{S}}+{\text{N}}{\text{A}}}$ where ${\displaystyle {\text{E}}}$ is the expected damage, ${\displaystyle {\text{S}}}$ is the source hit average damage, ${\displaystyle {\text{N}}}$ is the expected number of auto-attacks, and ${\displaystyle {\text{A}}}$ is the auto-attack average damage.

### Source hit average damage

Value used for source hit average damage.

### Auto-attack average damage

Value used for auto-attack average damage.