Arcane

Arcane is a stat in Bloodborne.

Description

In-Game Description

Attribute governing power of Arcane ATK. Determines whether or not you can use certain equipment.

General Information

Arcane is the stat that allows hunters to be able to use Hunter Tools (with the exception of the Madara's Whistle). It will dictate just how powerful these Hunter Tools are, and will boost the Item Discovery stat slightly. Additionally, the stat governs a boost to both the elemental damage types, Bolt and Fire, and it will also boost Arcane Damage on Weapons. Note though that all trick weapons in-game have a scaling on Arcane, but few have good scaling. This means that weapons with the best Arcane Scaling make the best elemental weapons as well.

For the most part, players should increase this stat if they wish to make use of some of the more passive Hunter Tools, which are the ones that will aid in a defensive position towards combat and to boost the natural damage of weapons they might prefer to keep as elemental weapons.

Players who wish to make full use of Arcane builds should be drawn naturally to Strength weapons as the most powerful weapons that have a focus on Arcane also focus on Strength. It has the same symbiosis as the relationship between Skill and Bloodtinge. Weapons that have split damage (additional damage other than physical), can never be turned into fully elemental damage, though.

If players wish to take a more casual approach to Arcane, then all they must do is simply possess 15 Arcane, since this will allow them access to the most basic and defensive Hunter Tools, not to mention that the ones at the player's disposal within this level of their Arcane stat are completely irrelevant in terms of scaling.

Early Arcane Build Tips

At the beggining of the game, players should prioritize getting the Flamesprayer from Gilbert, by slaying Father Gascoigne. Though it scales poorly with the stat, it still scales somewhat and is rather powerful, even against enemies that lie outside the beast-type. To maximize damage against them though, you should use a Saw Spear or Saw Cleaver, simply because of the fast charging attack for backstabs, which you can then finish with a burst of flames from the Flamesprayer.
- A +3 Flamesprayer will end the most deadly enemies at the start of the game, and not only that, but its damage can be boosted with the aid of the aforementioned backstabs, with Oil Urns, and with Bone Marrow Ash. It even stays relevant for most of the later game, though it loses some of it effectiveness against enemies that aren't weak to Fire.
Players should then focus on getting to Old Yharnam to slay the Blood-starved Beast and getting the Pthumeru Chalice. This allows access to the Watchdog of the Old Lords, and killing it twice is reccomended for its Radial Fire Blood Gems.
After defeating Vicar Amelia and the Witch of Hemwick, you should first go to Cainhurst Castle to obtain the Executioner's Gloves. This Hunter Tool will demolish Rom at point blank range, provided you have leveled your Arcane stat enough, of course.

Hunter Tools

Hunter Tools are available to the player once they are found, but only if they have the necessary Arcane requirement to use it. Some are defensive, while others are offensive.

These are the Defensive type of Hunter Tools:

Messenger's Gift (Req: 10 Arcane/Cost: 1 QS) - Transforms the player into a Messenger Note. Its effects are indefinite until the player sprints, or performs any action. It is easy to tell if a player is hiding as a message since the disguise is as if players were on top of the message.
Old Hunter Bone (Req: 15 Arcane/Cost: 4 QS) - Allows a hunter to perform the "art of quickening". It increases invincibility frames when dodging, and makes players vanish in-between dodges (similar to the Simpleton's Ring from Dark Souls 2). Last for about 15 seconds.
Beast Roar (Req: 15 Arcane/Cost: 2 QS) - The player will brace its own body and produce a roar, unleashing a shockwave that bounces almost any thrown object at the player, and will cause any small enemy to be thrown violently at the ground (similar to the Force Miracle from Dark Souls).
Choir Bell (Req: 15 Arcane/Cost: 7 QS) - This Tool will heal the caster, and any co-operators near its vicinity, the amount of health restored is increased with higher levels of Arcane.

These are the Offensive type of Hunter Tools:

Empty Phantasm Shell (Req: 15 Arcane/Cost: 3 QS) - A weapon buff, similar to Fire Paper or Bolt Paper. Great for players who want a more casual approach to Arcane.
Blacksky Eye (Req: 16 Arcane/Cost: 1 QS) - DLC item that shoots a fast projectile at an opponent, deals less damage than Augur of Ebrietas, but has more range than any firearm. Can be used to finish off opponents at a range.
Augur of Ebrietas (Req: 18 Arcane/Cost: 1 QS) - Players will summon a portion of Ebrietas to deal damage to enemies and knock them to the ground. Has limited range and takes a while to reach its maximum distance. Sends most enemies flying and can parry if timed correctly upon an enemy attack. When it strikes the back of an opponent, it will guarantee the opportunity for a backstab visceral attack.
Executioner's Gloves (Req: 20 Arcane/Cost: 3 QS) - Summons 3 pursuing orbs of arcane that have a lot of range, great tracking, but poor speed. Ideal against fleeing enemies and in tight spaces. Also useful against large bosses with specific weak spots such as their head.
Tiny Tonitrus (Req: 25 Arcane/Cost: 6 QS) - Summons many consecutive pillars of lightning in a straight line, dealing massive damage and possibly hitting multiple opponents. It is, however, extremely easy to dodge, but excels in tight corridors. It has about the same reach as the Blacksky Eye's projectile, and is incredibly powerful against the Kin -- often one-shotting most Kin mobs.
Accursed Brew (Req: 30 Arcane/Cost: 2 QS) - The player will throw a purple Arcane projectile that will explode midair after a short range, similar to a Molotov Cocktail, although it has a much faster projectile speed.
A Call Beyond (Req: 40 Arcane/Cost: 7 QS) - Unleashes a myriad of small Arcane orbs, some of which will track opponents, while others simply surround the caster and blast around him. It is an incredibly powerful tool and should be used mostly in tight situations, such as when being surrounded. It will essentially nuke everything inside a small room. It is extremely hard to dodge and deals insane damage. Rolling is recommended.

Elemental Damage

It is of utmost importance to note that when a weapon is given an element, it will deal only elemental damage, and any sort of thrust attack, or blunt attack multipliers are taken off the equation. Bonuses from Serrated Weapons and Righteous Weapons are still applicable, as it is an inherent effect of the weapon.

Within the game there are three kinds of elemental damage, each with its advantages and disadvantages, though most of the enemies that are weak to each elements are usually obvious.

Fire - Deals additional damage to almost all beast type enemies and are arguably the best element to give to a weapon (preferably serrated) at an early stage. It also deals damage to some kin type enemies (like the Brainsucker). It is recommended to use it within the Ailing Loran Chalice Dungeons.
Bolt - Deals a great deal of damage to all kin type enemies, and is an obvious choice for weapons when delving in kin infested areas, such as the Isz Gravestone Dungeons. Also effective towards ethereal, ghostlike enemies such as the specters within Cainhurst (which are also vulnerable to Righteous Weapons).
Arcane - It is an element that is strange in nature, though most enemies are not resistant to it, some Kin enemies are, and some Great Ones as well. It is bizarrely effective against Pthumerians, and as such it is a great element when delving inside the vast majority of the Chalice Dungeons (the exception perhaps being Ailing Loran and some sections of Isz).

Weapons

As stated before, weapons don't necessarily need to have a good scaling in Arcane to make good elemental weapons, but it will help, the most relevant weapons for Arcane Builds will be divided in 3 categories:

-The Static Category, these weapons deal split damage in Physical and Elemental damage, however, the ones with split Arcane damage have minimal, and almost insignificant damage, while the others with elements can be further boosted as they are self-buffing:

Amygdalan Arm - Deals little arcane damage.
Blade of Mercy - Deals little arcane damage.
Burial Blade - Deals little arcane damage.
Boom Hammer - Deals only split Fire damage when transformed, with amazing extra damage. The buff will last until the player attacks, but is removed right after the attack.
Tonitrus - Deals split bolt damage with every strike. Bolt damage is significantly increased when transformed. The buff will only last for about 7 seconds.

-The Elemental Category, these weapons have only the highest Arcane scaling (B or A when maxed), can be changed into whatever element the player chooses, and can be switched at ease without any sort of problem:

Threaded Cane (B) - When in original form it deals Righteous damage (+20%), while transformed it deals Serrated damage.
Kirkhammer (B) - When in sword mode it deals Righteous damage (50%)
Ludwig's Holy Blade (A) - Both modes deal Righteous damage (50%)
Whirligig Saw (B) - In Saw mode it will deal Serrated damage.

-The Arcane Category, these weapons are made specifically to possess an impressive Arcane damage potential:

Logarius Wheel - (C) It is a weapon with great scaling in Strength (S), and when it is transformed you can spin the wheel, thereby buffing it, making it deal increased damage, only has 3 levels, however, for every spin it takes more health, the health can be regained from hitting an opponent. It is almost like an opposite face of a coin when compared to the Chikage, another weapon that drains health, but is rather for Skill/Bloodtinge builds. When the weapon is transformed, it quadruples the Arcane damage it has.
Holy Moonlight Sword - (C) Another weapon that is great for strength/Arcane builds as it will be possible to use a great, staggering moveset, in its regular form, however, when transformed, its strong attacks and special attacks will throw an arcane wave in the direction they are facing, dealing massive damage, but using up a QS bullet.
Kos Parasite - (A) A weapon that scales highly with Arcane, and is used as if you were bare handed. However, when combined with the Milkweed Rune it transforms entirely and has an entire new moveset, when you transform it while using the Milkweed Rune you will have tentacles sprouting from both hands. It has great potential as it has hyper-armor in its attacks, as if a strength weapon, and deals pure Arcane damage. On top of it all, it has great damage modifiers for different attacks and its special attack when two-handed is a powerful Arcane blast that burst from the users body, damaging everything around in a small, yet deadly radius.

Firearms

There are very few left hand weapons that use arcane scaling, however, the following are:

Flamesprayer - A weapon that uses flames by using Quicksilver Bullets every second. Scales poorly with Arcane, yet is very helpful in dealing with beasts.

Rosmarinus - A weapon that is like the Flamesprayer, however it shoots a special white mist. Scales very well with Arcane and has amazing damage potential when used with Bone Marrow Ash.
Hunter's Torch - Despite not being an actual firearm, it indeed scales with Arcane, and at the beginning of the game it is invaluable if players cannot get their hands on fire blood gems. Should it be upgraded enough, it can almost one shot most beasts in Old Yharnam and three shot the werewolf like beasts and as such is very useful for early game characters.

Blood Gems

Perhaps the greatest obstacle to overcome, in an Arcane build, lies in finding the proper elemental blood gems. Within the world of Bloodborne, there are extremely low amounts of elemental blood gems to be found, and most of them are extremely weak at that. While physical damage builds and Bloodtinge builds can rely on Physical Attack Up Blood Gems, Arcane builds have to go out of their way and delve into the deepest and hardest of the Chalice Dungeons to find decent blood gems.

Additionally, one should be careful in its weapon variant choice, if wanting to add Arcane into a weapon, then make sure to find a variant with a Triangular Gem Slot, as the best Arcane gems are found in triangular shape. If adding Fire or Lightning, then the Waning Gem Slot variant of weapon is what one should go for.

There is also a type of gem that is very good and yet very rare, but that can be found once or twice within the main game, the Nourishing Gem. This gem's effect is ATK Up, this means it boosts all sources of damage, and is great for weapons with split damage, like the Amygdalan Arm, Tonitrus, Holy Moonlight Sword, or the Logarius Wheel.

The best farm spots for gems are indeed within the chalice dungeons, and it is best if players look online for the best glyphs for root chalice dungeons, simply question what the shape, and the effect are, and it will be easy to find.

However, within the Old Hunters DLC, there are many decent non-radial elemental blood gems, but near the Lighthouse Hut Lamp there are hooded enemies that carry a very large staff to cast lightning on enemies, this enemy in particular drops high quality (for campaign) Radial Bolt Bloodgems and even drop it in Triangular Shape occasionally. There are plenty of these enemies around the Lamp and they all have excellent drop rates.

The best Waning Fire/Bolt Gems are found in Loran, particularly from the Silverbeasts, either the mob or boss variant.

As for Triangular Arcane Blood Gems, players could look into the Great Isz Chalice Dungeon, even if you should play in the regular, non-root version, there are still enemies and bosses that drop them at good rates and quality.

Notes

Pthumerians are, strangely, very vulnerable to Arcane damage.

Trivia

In the Alpha of bloodborne the icon use for Arcane was originally going to be an apple instead of a star.
The word "Arcane" is related to something secret, mysterious and obscure, and in this case it seems to imply a certain type of knowledge of the unknown. By increasing it, the Discovery stat is raised and as such your chance of finding items on enemies, this could mean that Arcane is a sort of Insight that allows you noticed things you otherwise wouldn't have seen.
In Bloodborne there are, interestingly, two different colors that Arcane damage takes, one is blue and is synonymous with the cosmos; but the other one, is a mixture of both red and purple, indicating that there is something severely wrong with the nature of the things that manifest that type of Arcane. Items that possess such strange effect include: the Logarius' Wheel, the Executioner's Gloves and the Accursed Brew. In fact, the thing they all share in common is that they are "Cursed Items", for a lack of a better term.
- This theory is further verified as several bosses in the game will produce this type of "Accursed Arcane".