Arc

ArcSpell, Chaining, Lightning
Mana Cost: (9-26)
Cast Time: 0.80 sec
Critical Strike Chance: 5.00%
Damage Effectiveness: 90%Requires Level 12An arc of lightning stretches from the caster to a targeted enemy and chains on to other nearby enemies. Each time the main beam chains it will also chain to a second enemy, but that secondary arc cannot chain further.Per 1% Quality:
0.5% chance to Shock enemiesDeals (7-152) to (37-862) Lightning Damage
10% chance to Shock enemies
Chains +(4-7) Times
(10-29)% increased Effect of Shock
15% more Damage for each remaining ChainPlace into an item socket of the right colour to gain this skill. Right click to remove from a socket.Acquisition
Level: 12Purchase Costs

Normal

1x Orb of Transmutation

Sell Price
1x Scroll FragmentMiscellaneous
Item class: Active Skill Gems
Metadata ID: Metadata/Items/Gems/SkillGemArc

For the Vaal-themed counterpart, see Vaal Arc.

Arc is a lightning spell that creates a chaining pulse.

Skill functions and interactions

• Since it is not a projectile, Arc cannot Pierce SupportPierce SupportSupport, Projectile
  Icon: p
  Mana Multiplier: 110%Supports projectile skills.Per 1% Quality:
  Supported Skills deal 0.5% increased Projectile DamageProjectiles from Supported Skills Pierce (2-4) additional Targets
  Supported Skills deal (0-19)% more Projectile DamageThis is a Support Gem. It does not grant a bonus to your character, but to skills in sockets connected to it. Place into an item socket connected to a socket containing the Active Skill Gem you wish to augment. Right click to remove from a socket. or Fork SupportFork SupportSupport, Projectile
  Icon: Y
  Mana Multiplier: 130%Requires Level 31Supports projectile skills, making their projectiles fork into two projectiles the first time they hit an enemy and don't pierce it.Per 1% Quality:
  Supported Skills deal 0.5% increased Projectile DamageSupported Skills deal (30-11)% less Projectile Damage
  Supported Skills ForkThis is a Support Gem. It does not grant a bonus to your character, but to skills in sockets connected to it. Place into an item socket connected to a socket containing the Active Skill Gem you wish to augment. Right click to remove from a socket., and it cannot be supported with GreaterGreater Multiple Projectiles SupportSupport, Projectile
  Icon: P
  Mana Multiplier: 165%Requires Level 38Supports projectile skills.Per 1% Quality:
  Supported Skills have 0.5% increased Attack Speed
  Supported Skills have 0.5% increased Cast SpeedSupported Skills fire 4 additional Projectiles
  Supported Skills deal (35-26)% less Projectile DamageThis is a Support Gem. It does not grant a bonus to your character, but to skills in sockets connected to it. Place into an item socket connected to a socket containing the Active Skill Gem you wish to augment. Right click to remove from a socket. or LesserLesser Multiple Projectiles SupportSupport, Projectile
  Icon: l
  Mana Multiplier: 140%Requires Level 8Supports projectile skills.Per 1% Quality:
  Supported Skills have 0.5% increased Attack Speed
  Supported Skills have 0.5% increased Cast SpeedSupported Skills fire 2 additional Projectiles
  Supported Skills deal (25-16)% less Projectile DamageThis is a Support Gem. It does not grant a bonus to your character, but to skills in sockets connected to it. Place into an item socket connected to a socket containing the Active Skill Gem you wish to augment. Right click to remove from a socket. Multiple Projectiles. Supporting Arc with Chain SupportChain SupportSupport, Chaining, Projectile
  Icon: c
  Mana Multiplier: 150%Requires Level 38Supports projectile skills, and any other skills that chain.Per 1% Quality:
  Supported Skills have 1% increased Projectile SpeedSupported Skills Chain +2 times
  Supported Skills deal (50-31)% less Damage with HitsThis is a Support Gem. It does not grant a bonus to your character, but to skills in sockets connected to it. Place into an item socket connected to a socket containing the Active Skill Gem you wish to augment. Right click to remove from a socket. will result in additional chains.
• Arc will chain to a random target within a specified radius centered on last target struck. Arc cannot chain back to the same target immediately, and must bounce one more time before chaining to the previous target.
• Arc, when not cast at any enemy, will target the nearest one within the skill's range.
• Can be used in left mouse button slot to cast and move.
• Spell Echo will be able to cast it twice instead of just one at a time.

Gem level progression

Level			Mana Cost	Lightning Damage	# Chains	Shock Effect	Exp.	Total Exp.
1	12	33	9	7 to 37	4	10%	0	0
2	15	39	10	8 to 47	4	11%	15,249	15,249
3	19	48	11	11 to 61	4	12%	41,517	56,766
4	23	56	12	14 to 80	4	13%	81,983	138,749
5	27	64	13	18 to 101	4	14%	147,968	286,717
6	31	73	14	23 to 128	5	15%	250,557	537,274
7	35	81	16	28 to 159	5	16%	405,086	942,360
8	38	88	16	33 to 187	5	17%	447,718	1,390,078
9	41	94	17	39 to 218	5	18%	615,318	2,005,396
10	44	100	18	45 to 254	5	19%	834,639	2,840,035
11	47	106	19	52 to 295	6	20%	1,570,760	4,410,795
12	50	113	20	60 to 342	6	21%	1,633,987	6,044,782
13	53	119	21	70 to 395	6	22%	2,151,030	8,195,812
14	56	125	22	80 to 456	6	23%	2,812,189	11,008,001
15	59	132	23	92 to 524	6	24%	5,099,360	16,107,361
16	62	138	24	106 to 602	7	25%	9,400,731	25,508,092
17	64	142	24	116 to 659	7	26%	15,273,366	40,781,458
18	66	146	25	127 to 721	7	27%	26,286,582	67,068,040
19	68	151	25	139 to 789	7	28%	62,890,590	129,958,630
20	70	155	26	152 to 862	7	29%	212,046,017	342,004,647
21	72	159	26	166 to 942	8	30%	N/A	N/A
22	74	N/A	26	181 to 1028	8	31%	N/A	N/A
23	76	N/A	27	198 to 1122	8	32%	N/A	N/A
24	78	N/A	28	216 to 1223	8	33%	N/A	N/A
25	80	N/A	29	235 to 1333	8	34%	N/A	N/A
26	82	N/A	30	256 to 1453	9	35%	N/A	N/A
27	84	N/A	30	279 to 1582	9	36%	N/A	N/A
28	86	N/A	30	304 to 1721	9	37%	N/A	N/A
29	88	N/A	31	330 to 1873	9	38%	N/A	N/A
30	90	N/A	32	359 to 2036	9	39%	N/A	N/A
31	91	N/A	32	375 to 2123	10	39%	N/A	N/A
32	92	N/A	32	391 to 2214	10	40%	N/A	N/A
33	93	N/A	33	407 to 2308	10	40%	N/A	N/A
34	94	N/A	33	424 to 2405	10	41%	N/A	N/A
35	95	N/A	33	442 to 2507	10	41%	N/A	N/A
36	96	N/A	33	461 to 2613	11	42%	N/A	N/A
37	97	N/A	34	480 to 2722	11	42%	N/A	N/A
38	98	N/A	34	501 to 2837	11	43%	N/A	N/A
39	99	N/A	34	522 to 2955	11	43%	N/A	N/A
40	100	N/A	35	543 to 3079	11	44%	N/A	N/A

Item acquisition

Quest reward

This item is given as quest reward for the following quests:

Class →	Witch	Shadow	Ranger	Duelist	Marauder	Templar	Scion
Quest ↓
The Siren's Cadence Act 1	✓	✗	✗	✗	✗	✗	✗

Vendor reward

This item can be bought at the listed npc vendors after completing the following quests:

Class →	Witch	Shadow	Ranger	Duelist	Marauder	Templar	Scion
Quest ↓
The Siren's Cadence Act 1 Nessa	✓	✓	✗	✗	✗	✓	✗
A Fixture of Fate Act 3 Siosa	✓
Fallen from Grace Act 6 Lilly Roth	✓

Related helmet enchantments

The following helmet enchantments affect Arc.

Name		Stats	Spawn Weighting
EnchantmentArcDamage1	66	25% increased Arc Damage	helmet 100 default 0
EnchantmentArcDamage2	75	40% increased Arc Damage	helmet 75 default 0
EnchantmentArcDamagePerChain1__	66	Arc deals 8% increased Damage for each time it has Chained	helmet 100 default 0
EnchantmentArcDamagePerChain2	75	Arc deals 12% increased Damage for each time it has Chained	helmet 75 default 0
EnchantmentArcNumOfAdditionalProjectilesInChain2	75	Arc Chains an additional time	helmet 75 default 0
EnchantmentArcShockChance1	66	Arc has +20% chance to Shock	helmet 100 default 0
EnchantmentArcShockChance2	75	Arc has +30% chance to Shock	helmet 75 default 0

Microtransactions

The list below shows microtransactions for Arc.

Item	Effect(s)
Automaton Arc Effect Automaton Arc EffectArc SkinYour Arc becomes an Automaton Effect.	Your Arc becomes an Automaton Effect.
Purple Arc Purple ArcArc Skin Stack Size: 20Your Arc becomes a Purple Effect.	Your Arc becomes a Purple Effect.
Radiant Arc Radiant ArcArc SkinYour Arc becomes a Radiant Effect.	Your Arc becomes a Radiant Effect.

Version history

Version	Changes
3.3.0	Now has an added damage effectiveness of 90% (up from 70%). Now deals 7-37 lightning damage at gem level 1 (up from 2-35), up to 152-862 lightning damage at gem level 20 (up from 47-886). Now deals 15% more damage for each remaining chain. Can now split to an extra enemy whenever it chains. These splits cannot then chain. Chains 4 times at level 1, up to 7 times at level 20.
2.1.0	Damage increased by around 20% higher at level 20. In addition to having more damage, Arc now increases in number of chains more often as it levels up. At level 20, it chains seven times. Previously this was five.
2.0.0	Damage reduced slightly at all levels. At player level 68, it should deal approximately 8% less damage.
1.2.0	We have reduced the damage by 15% at all levels. Got +1% to critical hit chance bringing it to 5%
1.1.2	ArcArcSpell, Chaining, Lightning Mana Cost: (9-26) Cast Time: 0.80 sec Critical Strike Chance: 5.00% Damage Effectiveness: 90%Requires Level 12An arc of lightning stretches from the caster to a targeted enemy and chains on to other nearby enemies. Each time the main beam chains it will also chain to a second enemy, but that secondary arc cannot chain further.Per 1% Quality: 0.5% chance to Shock enemiesDeals (7-152) to (37-862) Lightning Damage 10% chance to Shock enemies Chains +(4-7) Times (10-29)% increased Effect of Shock 15% more Damage for each remaining ChainPlace into an item socket of the right colour to gain this skill. Right click to remove from a socket. and Vaal ArcVaal ArcVaal, Spell, Chaining, Lightning, Duration Souls Per Use: 25 (N) / Can Store 1 Use(s) Soul Gain Prevention: 6.000 sec Cast Time: 0.80 sec Critical Strike Chance: 5.00% Damage Effectiveness: 180%Requires Level 12A shocking arc of lightning stretches from the caster to a targeted enemy and chains to other nearby enemies. Each time the beam chains it will also chain simultaneously to a second enemy, but no enemy can be hit twice by the beams. Also grants a buff making you lucky when damaging enemies with Arc for a short duration.Per 1% Quality: 1.5% increased Shock Duration on enemiesDeals (38-924) to (64-1539) Lightning Damage 100% chance to Shock enemies Chains +(5-9) Times 100% increased Effect of Shock 100% increased Shock Duration on enemies 15% more Damage for each remaining Chain Base duration is 4 seconds Modifiers to Buff Duration also apply to this Skill's Soul Gain Prevention CorruptedPlace into an item socket of the right colour to gain this skill. Right click to remove from a socket. have had their damage increased by 60%. Arc and Vaal Arc can now no longer chain back to the same target immediately, but must now bounce one more time. Arc now increases in chain counts as the gem increases in level.
1.0.0	Reduced the mana cost. Damage has been increased by around 23%.
0.11.1	Spells with Damage Effectiveness no longer have their own damage affected by Damage Effectiveness. Damage values on these skills have been updated to reflect this.
0.9.13	Arc has been added to the game.