Rune Arm

Overview
Rune Arm (or Arm Cannon) is new kind of equipment implemented with Update 11 and the Artificer class. It goes into secondary weapon/off hand slot and requires Artificer Rune Arm Use feat (Artificer level 2 class feat) to use.

Rune Arms can be used in the offhand (with crossbow). The Rune arm has unique magical properties such as: adding magical weapon damage to the main hand, magical enhancements, and being craftable via Cannith Crafting system.

For the crafting purpose, the Craftable Rune Arm (+X) property written on a Rune Arm defines maximum enhancement level it would permit. On a Rune Arm crafting shards are applied as if it was a trinket, and adding crafting enhancements raises the minimum level requirement accordingly (2 levels per +1 potential).

The Rune Arm also functions as a weapon as a free action (not restricting the users abilty to cast or attack). The weapon uses Charges with five tiers, and these charges increase in damage the higher the tier (Rune Arms have a max tier level). Charges can be added standing still or while moving limited by the "Stable Charge Tier".

Rune Arms are currently only acquired by finishing certain quest chains, or in certain chests already known for dropping named and/or rare loot, such as the three dragon chests in Gianthold Tor; there are currently no randomly generated Rune Arms. The complete list of known Rune Arms, as well as their location, are below.

How it works

 * Can be worn together with one-handed weapons and crossbows (not bows)
 * Tapping the Alt button will start charging it up, tapping it again fires it.
 * You can Toggle the Rune Arm Use feat on while on an actionbar to make it keep autocharging.
 * Damage will be affected by Artificer level and charge tier.
 * Rune Arms will give a bonus elemental damage to the weapon in your main hand.
 * Blocking with a charge reduces the charge to it's maximum stable tier.

List of named Rune Arms
As of Update 11, named Rune Arms have been added to almost all reward list across the game (Sharn Syndicate being the exception, which doesn't seem to award one) and to some other named loot/raid chest. Items are Bound to Account unless otherwise noted.

Max Charge Tier 2:
 * Candlelight - Catacombs ML3
 * Chulchannad's Claw - Phiarlan Carnival ML5
 * Flame Warden - The Lost Seekers ML1
 * Flicker - The Seal of Shan-To-Kor ML3
 * Khyber's Fury - Assault on Splinterskull ML5
 * Thought Spike - Redemption in Korthos Island (BtC) ML1

Max Charge Tier 3:
 * Chimera's Breath - Sentinels of Stormreach ML5
 * Coronach - Delera's Tomb ML7
 * Hand of the Tombs - The Chamber of Raiyum (treasure chamber chest, BtC on equip) ML9
 * Recoyle - Ruins of Threnal ML9
 * The Devourer's Hunger - Cult of the Six ML7, (note: Superior Glaciation IV instead of Greater Freeze)
 * The Disciplinator - Vault of Night (raid chest, BtC) ML9
 * The Pea Shooter - Into the Deep in The Red Fens ML7
 * Trial by Fire - Attack on Stormreach ML11

Max Charge Tier 4:
 * Arcing Sky - Gianthold Tor (Blue Dragon chest) ML13
 * Chill of Winter - Gianthold Tor (White Dragon chest) ML13
 * The Turmoil Within - Gianthold Tor (Black Dragon chest) ML13
 * Titan's Fist - The Titan Awakes (raid chest, BtC) ML11

Max Charge Tier 5:
 * Animus - Devil Assault on all difficulties ML19
 * Glorious Obscenity - Reign of Madness ML17
 * Lucid Dreams - The Mindsunder (Disc-locked end chest) ML19
 * Tira's Splendor - Garamol (rare encounter in The Subterrane) ML17
 * Toven's Hammer - The Master Artificer (raid chest, BtC) ML19