Archlight

Arclight is a demonbane weapon requiring level 75 Attack to wield. An upgraded variant of Darklight, Arclight features an enhanced passive effect in addition to modest improvements in attack bonus and speed.

If Arclight is lost, it can be replaced by paying Sir Prysin 1,000 coins for Darklight and enhancing it with ancient shards again. Players can possess multiple copies of Arclight.

After reading Duradel's notes, at level 74 Smithing, players can use either a fully charged or infused Arclight with a tormented synapse to upgrade the weapon to Emberlight.

Arclight can be made by using Darklight on the altar in the centre of the Catacombs of Kourend while three ancient shards are in the inventory. Attempting to make the Arclight without the altar results in a game message: You require additional power from the catacombs altar to create Arclight.

Arclight retains Darklight's special attack, Weaken, which consumes 50% of the player's special attack energy and lowers the opponent's Strength, Attack, and Defence levels by 5% (10% for demons) of their base level + 1.^[1]

The accuracy roll for Weaken is made against an opponent's stab defence,^[2] and its drain effect only applies to successful hits.

Weaken will stack additively upon successful hits unlike the dragon warhammer, which stacks multiplicatively. Two successful special attacks thus reduce an opponent's Strength, Attack, and Defence by 10% + 2, or 20% + 2 against demonic targets.

When used against demonic monsters, Arclight provides a 70% increase in accuracy and damage. Some demons have modified demonbane effectiveness, which can either reduce or increase this bonus; for example, Duke Sucellus has 70% demonbane effectiveness, reducing the bonus to 49% accuracy and damage. Like Darklight, Arclight also counts as a piece of silver weaponry, and can therefore damage tier 2 vampyres, while gaining a 10% damage bonus against tier 1 vampyres.

This means that in certain cases, Arclight can have higher damage output than typical high-damage weapons such as the blade of Saeldor or scythe of Vitur when fighting K'ril Tsutsaroth or demonic gorillas.

Beginning with 1,000 charges after creation, it gains an additional 333 charges for every ancient shard added, or 1,000 if three are added simultaneously. Players can configure the charges while the weapon is in their bank by right-clicking on Configure-Charges, as long as players have the required materials. Arclight has a maximum capacity of 10,000 charges, requiring 30 ancient shards to fully charge.

One charge is consumed for each successful hit, excluding those from its special attack. If all charges are consumed, it will transform into an inactive variant which functions identically to Darklight.

After reading Duradel's notes, at level 74 Smithing (boosts are allowed), players can use either a fully charged or infused Arclight with a tormented synapse to upgrade the weapon to Emberlight. Requiring level 77 Attack to equip, it offers increased base combat stats and does not degrade. Infusion and charges can be combined to reach the requirement for upgrading (for example, 7,000 charges and 30% infusion). If the combined total of infusion and charges exceeds the equivalent of 10,000 charges, the excess charges will be wasted. The upgrade is done by using the synapse on an anvil while having the Arclight and a hammer in the player's inventory. Trying to use the tormented synapse directly on the Arclight results in a message saying You try to attach the synapse to the sword. The blade sizzles for a moment, but the synapse just slides off it again..

Arclight possesses a unique infusion mechanic in which each charge consumed increases the infusion in return, with a fully charged and spent Arclight corresponding to 100% infusion. This mechanic allows spent charges to count towards the 10,000 required for upgrading into the Emberlight, though a fully infused Arclight will still consume charges. Infusion progress will not be lost if Arclight runs out of charges.

The current percentage of infusion can be determined by right-clicking the "Check" option on Arclight. Since full infusion requires 10,000 charges, counting both infusion and unspent charges, each percent is equivalent to 100 charges for the purpose of upgrading. For example, at 7% infusion, 700 charges have been used, and 9,300 charges still need to be used to fully infuse.

• The bloody diary references how the Arclight is created. It is the only in-game source of information on creating it.
• A second Arclight can be created and will have 1,000 charges independent of any other Arclights in possession.
• Despite being an upgraded form of Silverlight and Darklight, Arclight has a lower strength bonus than either (12 → 13 → 8).
• Unlike Silverlight and Darklight, the Arclight can not be used as a mounted sword inside a player-owned house.
• It's possible to create an Arclight without completing Shadow of the Storm. If a player dies and reclaims Darklight from their grave, they can take it to the altar and imbue it there without claiming the experience and ending the quest. However, they will need to claim another sword from Sir Prysin in order to complete the quest.
• All of Arclight's model with the exception of the embedded Ancient shard is slightly translucent.