# Ava's accumulator

Ava's accumulator
Released12 December 2006 (Update)
MembersYes
Quest itemAnimal Magnetism
Properties
EquipableYes
StackableNo
OptionsWear, Commune
Worn optionsCommune
DestroyDrop
ExamineA superior bagged chicken ready to serve you, magnet in claw.
Values
Value0 coins
High alch0 coins
Low alch0 coins
Weight4.535 kg
Item ID10499

Ava's accumulator is a reward from Animal Magnetism if you have 50 Ranged or higher upon completion (players with lower than 50 Ranged will instead receive Ava's attractor). The accumulator can pick up a player's ranged ammunition after they fire it, and will also randomly attract metal items (steel arrows, darts, med helms, bars, nails and knives, iron ore, and toy mice) into the player's inventory. If the player's inventory is full, the attracted item will be dropped at their feet, unless the item can be equipped if that equipment slot is free i.e. knives, darts, arrows, steel med helm. Like all of Ava's devices, the accumulator will not work when metal torso armour (Ahrim's top included) is worn, as this will cause 'interference'. Proselyte and Shayzien both work with Ava's Devices.

Ava (found in Draynor Manor) will upgrade the attractor for anyone who obtains 50 Ranged after the quest for a price of 75 steel arrows, along with either 999 coins or an attractor (If you bring both coins and an attractor, the attractor will be used). After that, it can be upgraded to Ava's assembler (upon completion of Dragon Slayer II) for Vorkath's head and 75 mithril arrows, as well as 4999 coins or an Accumulator.

Upon dying, if it is not an item kept on death, it will be stored in the player's grave until reclaimed. If not reclaimed within an hour, it can be reacquired by speaking with Ava and purchased for 999 coins and 75 steel arrows. Multiple devices may be possessed at the same time.

The accumulator gives the second best Ranged attack bonus for the cape slot.

If ranged equipment is equipped, the steel arrows will be automatically generated into the arrow slot.

As with Ava's other devices, Ava's accumulator can be used on both Lanthus in the Castle Wars lobby and Nomad in the Soul Wars lobby to permanently activate the effect in the minigames.

The Ava's accumulator can be combined with the max cape to change its appearance by turning it into the accumulator max cape.

### Ammo recovery rate

The breakdown of the ammo recovery rate is as listed:

• Break on impact: 20%
• Drop onto floor: 8%
• Recovered automatically: 72%
 Attack bonuses +0 +0 +0 +0 +4 +0 +1 +0 +4 +0 +0 +0 +0% +0 List

## Cost saving benefits

The ammo retention of the accumulator results in ammunition being fired 3.57 times before it is lost, assuming it is not picked up from the ground. This means it is approximately three and half times cheaper than the price paid. Picking up ammo would make it equal to the Ava's Assembler's 80% ammo retention rate, where each ammunition is fired 5 times before it is destroyed.

Let ${\displaystyle p(n)}$ be the probability to shoot a single arrow exactly ${\displaystyle n}$ times and ${\displaystyle P(n)}$ be the probability to shoot a single arrow at most ${\displaystyle n}$ times.

${\displaystyle P(n)=p(1)+p(2)+...+p(n-1)+p(n)}$.

By definition ${\displaystyle p(1)=1}$ because a single arrow can always be shot once. Since the recovery rate for a single arrow is 0.72,

${\displaystyle P(n)=1+0.72+0.72^{2}+...0.72^{n-1}+0.72^{n}\implies \sum _{k=0}^{n}0.72^{k}}$.

The expected number of shots fired per arrow is then

${\displaystyle \sum _{k=0}^{\infty }0.72^{k}={\frac {1}{1-0.72}}=3.57}$.

## Changes

Date Changes
21 October 2020
(update)
• Ava's accumulator is no longer automatically protected upon a non-PvP death.
• The "Destroy" option was replaced with a "Drop" option.
14 October 2020
(update | poll)

Ava's accumulator is no longer destroyed upon a non-PvP death.

9 April 2015
(update)

You can now choose to buy-X devices at once when right-clicking Ava and selecting 'Devices'.

22 January 2015
(update | poll)

The device is now able to grab ammo whether or not an obstacle is in the way.

5 June 2014
(update)

Ava device ammo conservation no longer takes effect on F2P Worlds.

20 February 2014
(update | poll)

Players may now toggle the collection of random metal items by right-clicking the accumulator and selecting "Commune".

## Trivia

• If your inventory is full when the accumulator picks up a random metal item, it will instead be dropped to the floor. The exception to this rule is if the item that is picked up can be equipped into an empty equipment slot. Thus, it is possible for players with 1 Defence to have steel helmets equipped, despite their level 5 Defence requirement.