Darksword

A Darksword (ダークサイドソード, Dākusaido sōdo^?, lit. Darkside Sword) is a Cursed Artifact Long Sword-class weapon that can be forged in Golden Sun: The Lost Age and Golden Sun: Dark Dawn. In both of its appearances, it has the highest base attack rating of any weapon in the Golden Sun series.

In Golden Sun: The Lost Age

Darksword (TLA)
Visual effect of Acheron's Grief
In-Game Description
"Cursed Sword: Unleashes Acheron's Grief" (TLA)
Trade Info
Weapon class	Long Sword
Buy value	24200
Sell value	18150
Artifact?	Yes
Statistic Boosts
Attack Boost	210
Unleash effect
Effect name	Acheron's Grief
Extra damage	76
Side effect	May inflict the target with Venom
Acquisition
• Forged from Dark Matter (TLA)

In The Lost Age, the Darksword can only be acquired by bringing a Dark Matter to the blacksmith in Yallam so that it may be turned into one of several items at random. The Darksword is picked at a rare 10% probability and forces you to buy it from the blacksmith for 24,200 coins before he can forge something else. The other items, for the record, are the Demon Circlet, Fear Helm, Stealth Armor, and Terra Shield.

The earliest point you can get a Dark Matter is by winning against Karst and Agatio at the end of Jupiter Lighthouse (a difficult battle the game allows you to lose without blocking off your progress through the plot). A second Dark Matter can be found in Prox, the final village. Once you get the Teleport Psynergy from Mars Lighthouse, you can warp into Yampi Desert Cave and find one Dark Matter in a chest, and you can infinitely farm the Wonder Birds of Islet Cave for their potential Dark Matter drops. Finally, one more Dark Matter can be found in Anemos Inner Sanctum, the extra-hard bonus dungeon that requires having all 72 Djinn from both GBA games in one password-enhanced file.

As a Long Sword, the Darksword can be equipped by Felix, Piers, Isaac, and Garet. Equipping this cursed item will inflict an equipment curse upon said Adept that renders him physically incapable of de-equipping it until you pay a Healer at a Sanctum to separate it from him. Also, if said Adept is not equipped with the Cleric's Ring, he will risk getting immobilized with every attempt at carrying out a battle command.

The Darksword's Unleash effect, Acheron's Grief (アケロングリーフ, Akeron gurīfu^?), is equivalent to a standard attack with 76 points of flat damage added to the end result, and the overall damage is aligned with Venus. There is also a 55% chance that it will afflict the target with the Deadly Poison (or "Venom") status condition. Visually, Acheron's Grief resembles the wielder summoning a colossal purple-hilted sword that crashes straight down into the target's position, letting loose purplish-blue energy as if it were a water spout while the sword digs further into the ground. It will eventually detonate in a large explosion of dark energy, and the screen temporarily inverts its colors in tandem. It essentially resembles a purple-colored duplicate of the Gaia Blade's Titan Blade Unleash.

From the perspective of the endgame, a Darksword will falter despite its peerless Attack stat unless you use the password system to transfer the Cleric's Ring from the original Golden Sun; this ring prevents the equipped user from occasionally failing to do anything with a given action. Presuming you have the ring equipped, the Darksword will prove itself strong but surprisingly lacking in impact without the proper setup and approach to using it. Having the highest base attack rating of all weapons in the game means that dealing any physical attack with this weapon other than proccing the Unleash (like casting Odyssey or some other Elemental Physical Attack Psynergy) will be more damaging than if you were to deal those exact same attacks with any other weapon.

However, a weapon's Unleash is typically its most defining aspect, and the Darksword faces rather overwhelming competition from a specific category of endgame-tier weapons that sport Unleashes that outright multiply the damage inflicted: the Masamune, Excalibur, Tisiphone Edge, and especially the Sol Blade. Acheron's Grief has the highest added damage bonus of any Unleash on a weapon that can be wielded by a "Warrior"-style Adept, and its chance to inflict Deadly Poison is both powerful and desirable when used against the toughest random monsters. (Technically, the Atropos' Rod and Lachesis' Rule feature even higher bonus damage values for their Unleashes, but both can only be equipped by "Caster"-style Adepts.) Bosses, on the other hand, always have Luck ratings preventing them from being afflicted by conditions that would fell them in a few turns otherwise, which makes Acheron's Grief only amount to a good amount of set flat damage when it procs against them.

The Attack stat of the Darksword is most effectively leveraged by using a different attack that applies a solid multiplier to the resulting damage. Various Djinn use damage multipliers instead of flat damage, like Echo's +60% damage and Geode's +90% damage, and the Ronin's unique Quick Strike Psynergy deals +80% damage and can be used much more easily. This is already a very powerful class to begin with, and Quick Strike would allow Garet to reliably perform a strong single-target strike every turn, limited only by his PP reserves. In a much more niche yet potent setup, the item-based Necromage class can cast Call Dullahan to deal a physical attack that triples the resulting damage; however, the Necromage requires a very unusual mixture of elemental Djinn to be Set and features heavily reduced HP, Attack, and Defense modifiers.

In Golden Sun: Dark Dawn

Darksword (DD)
The DS model of the Darksword
In-Game Description
"Weapon: Long Sword (Cursed)" (DD)
Trade Info
Weapon class	Long Sword
Buy value	24200
Sell value	18150
Artifact?	Yes
Statistic Boosts
Attack Boost	210
First Unleash effect
Effect name	Mortal Danger
Extra damage	28
Side effect	May instantly fell the target
Second Unleash effect
Effect name	Spiral Assault
Extra damage	x1.3
Side effect	Hits each adjacent foe
Third Unleash effect
Effect name	Sky Diver
Extra damage	65
Side effect	May Stun the target
Fourth Unleash effect
Effect name	Acheron's Grief
Extra damage	76
Side effect	May inflict Venom
Acquisition
• Forged from Dark Matter (DD)

In Dark Dawn, the Darksword is obtained in much the same way as it was in The Lost Age: by bringing a Dark Matter to the Blacksmith at Champa and hoping it will randomly be forged into a Darksword instead of a different piece of cursed gear (which, in this game, are only the Demon Circlet and the Terra Shield). However, Dark Matter can only be found in the Dark Dawn version of Crossbone Isle; two pieces are found in chests, and the randomly appearing Minos Knight drops it at an extremely rare base rate of 1/256, improving only to 1/64 whenever one is slain by using the attack of an offensive Jupiter Djinni. This makes the Darksword, Demon Circlet, and Terra Shield exclusive to the game's postgame, severely limiting their functionality and making them irrelevant to the player's efforts to reach the end credits for the first time.

The Darksword, like all other weapons in Dark Dawn, now features a collection of four Unleashes that will be randomly picked between whenever the weapon is made to Unleash, and the additional three Unleashes are largely inferior to Acheron's Grief. The first Unleash is Mortal Danger (デスクライシス, Death Crisis^?), otherwise only seen on the Assassin Blade, which deals a Venus-aligned attack with 28 added damage and a 20% base chance to instantly fell the target. The second Unleash is Spiral Assault (スパイラルアタック, Spiral Attack^?), which deals a Jupiter-aligned attack that is 30% more damaging and additionally strikes each adjacent enemy for 80% of the overall force. The third Unleash is Sky Diver (スカイダイバー, Skydiver^?), another Jupiter-aligned attack that adds 66 damage and a 40% base chance to inflict the Stun status condition. Acheron's Grief, being the fourth and final Unleash in the list, takes the most time to unlock.

In the postgame, while Matthew should always stay equipped with the Sol Blade, it is a more open question whether you should give the Darksword and the Cleric's Ring to Tyrell (the only other Adept who can wield long swords). Generally, the best weapon for Tyrell to wield is a Levatine forged from a Mythril Silver, which is capable of a very powerful Unleash that multiplies damage by x2.4 and can ignore half of a target's Defense. A fully mastered Darksword is fairly likely to inflict either Stun or Venom because of it featuring both Sky Diver and Acheron's Grief, but both of these only apply to random monsters; bosses, which resist almost all secondary effects, are best dealt with using raw damage.

However, having access to the Darksword optimizes Tyrell's performance with the same "Quick Strike Ronin" build that could be used by Garet in the previous game. The fact so many weapons become less consistent in the Dark Dawn Unleash system due to getting bogged down by randomly chosen, weaker Unleashes drives up the value of the Quick Strike Psynergy, which can always be relied on to apply its x1.8 multiplier on command. While this would already be quite powerful using a 173-attack Levatine, using a 210-attack Darksword lets Tyrell deal Quick Strikes with 37 more base Attack modified by the Ronin's very high 160% Attack modifier. Tyrell can alternatively become the Master class and use its signature Annihilation Psynergy for its own x1.5 multiplier and the backing of the class' even higher 170% Attack modifier. (Annihilation being capable of instant kills makes that a stronger version of the Mortal Danger unleash, one that can be used without random chance threatening to perform a different attack.)

Cultural references

The real-world river Acheron ("stream of woe") was believed to lead into the underworld of Greek mythology by the ancient Greek civilization. The ferryman Charon was said to ferry the souls of the dead across this river to the afterlife, though later versions of the legend would claim that this took place at a decidedly more fictional river called the Styx.

Gallery of Dark Dawn unleashes

• 

  Mortal Danger

• 

  Spiral Assault

• 

  Sky Diver

• 

  Acheron's Grief