Mark of Darkness

Mark of Darkness
Released	16 June 2021 (Update)
Members	Yes
Level	59
Spellbook	Arceuus
Type	Combat
Experience	70
Runes	1 1
Casting speed	0 ticks
Cooldown	10 ticks
Quest	A Kingdom Divided
Description	Makes your offensive Arceuus spells more potent
Animation
Sound effect

Mark of Darkness is a spell within the Arceuus spellbook that requires level 59 Magic and the completion of A Kingdom Divided to be cast.

When under the effects of the spell, the caster will gain various buffs for a certain amount of time ( $(Y * 3) * 0.6$ seconds), where $Y$ is the player's base Magic level. If cast with a purging staff equipped, the duration is multiplied by five.

Casting the spell results in the message You have placed a Mark of Darkness upon yourself. The player will receive the following message 10 ticks before the spell expires: Your Mark of Darkness is about to run out.. An animation will play when the caster is no longer under the effects of the spell and the player will receive the message Your Mark of Darkness has faded away..

Mechanics

Players under the effects of the Mark of Darkness will temporarily gain the following buffs:

The bind chance of grasp spells is doubled, though the bind duration remains the same.
Corruption spells will always inflict corruption on the player's next successful hit, up from a 50% chance.
Demonbane spells will have doubled accuracy (+40%) and an additional 25% damage bonus against demons. This is calculated after the player's own magic damage bonuses from their equipment.
- If attacking with a purging staff, this is further doubled to an 80% accuracy and 50% damage bonus when under the effects of the Mark of Darkness.

Cost

Spell cost
Input	Cost
¹ ¹	507
Combo runes
¹	765

Changes

Date	Changes
27 August 2025 (Update)	The spell's base duration has been increased by 3x (e.g. at 99 Magic, the duration has been increased from 59.4 seconds to 2 minutes 58.2 seconds).
14 May 2025 (Update)	Mark of Darkness can now be recast before it expires.
24 July 2024 (Update)	The spell's duration is now increased by 5x when a purging staff is equipped.
30 August 2023 (Update \| poll)	The spell is now a self-casting spell rather than a target-casting spell. The spell's description has been changed; previously, it was "Makes your target vulnerable to the effects of offensive Arceuus spells" Players will now receive a message 10 ticks before Mark of Darkness expires.
30 June 2021 (Update)	An animation will now play when a target is no longer under the effects of the Mark of Darkness spell.