Masamune

The Masamune is a Light Blade-class Artifact weapon found in Golden Sun: The Lost Age and Golden Sun: Dark Dawn.

Basic description by game
In all its appearances, the Masamune increases the wielder's attack by 161. It can be sold for 12300 coins, and subsequently re-bought for 16400 coins.

In The Lost Age, it is found in a treasure chest in Yallam, but the Force Psynergy is required to reach the chest, meaning the Masamune is not available until after Jupiter Lighthouse. Being a Light Blade, it can be equipped by Isaac, Felix, Garet, Jenna, Ivan, and Piers. The Masamune's Unleash attack is Rising Dragon, which activates at a rate of 40% (notable, as most Unleashes activate at a rate of 35%). Rising Dragon converts all damage to Mercury damage and attacks with an additional 62 damage points. In addition, there is a chance of doing twice the normal amount of damage. Visually, Rising Dragon resembles a light blue cloud with the shape of a dragon's head at the front streaming from the attacker and arcing slightly before striking the target from above. If Rising Dragon does double damage, a second, identical cloud follows, only this cloud strikes from below.

In Dark Dawn, the Masamune can be obtained in the Yamata Ruins after Himi has joined the party. The Masamune is given three Unleashes: Double Attack, Combat Dance, and its trademark unleash Rising Dragon. Double Attack is a Jupiter-based Unleash that multiplies damage by 1.6. Combat Dance is a non-elemental attack that has a damage multiplier of 1.5. Rising Dragon still does Mercury damage with an additional 62 points and a chance to double the damage. However, Rising Dragon now has a range of up to 3 targets each time it activates.

The Lost Age
The Masamune is a powerful weapon that can be equipped to almost anyone. However, it is only accessible in a password-enhanced game, specifically those that have transferred the Orb of Force. When this requirement is met, the Masamune is easily obtainable. However, it remains unavailable until late into the game, meaning it normally serves as a placeholder for more powerful weapons like Tisiphone Edge and Excalibur, both of which are capable of attacking for three times their normal damage. However, in terms of raw power, no weapon can outdo a two-strike Rising Dragon from the Masamune until the above mentioned weapons or the Sol Blade are acquired. Even then, it is worth considering that Masamune does water damage, not earth or wind.

The Masamune is the most powerful Mercury-based weapon that Piers can equip. Although it's a Light Blade, both its base attack and bonus Mercury damage from its unleash are higher than its nearest contender, the Mythril Blade. On top of this, the Masamune has a chance to do double damage, pushing it well in front of the Mythril Blade; however, it is still inferior to several weapons of different elements available at the end of the game such as the Tisiphone Edge and Excalibur. Since it is the most powerful Mercury-based weapon available to Piers, however, it is still a solid choice for him if placed in a Mercury-based class. In addition to this, the weapon's notable unleash rate (which adds 5%) can allow for a 99% unleash setup, akin to a Venus Adept wielding the Sol Blade. In Piers's case, an appropriate setup would consist of the Mythril Helm, Riot Gloves, Hyper Boots, and Mythril Clothes instead of the Valkyrie Mail to account for the naturally higher unleash rate.

Dark Dawn
The Masamune serves as an excellent choice, due to its easy accessibility and general power. It possesses one of the strongest Mercury-based unleashes in Rising Dragon, second to the Sagittarius Bow's Blue Comet, and is given an improvement in its potential to hit multiple targets for double damage. Meanwhile, Double Attack and Combat Dance have good damage multipliers, allowing for decent damage at later stages of the game, where Attack-based offenses begin to out-power Psynergy. These qualities make it an ideal endgame weapon for Amiti, particularly if he is in his base class.

While the Sagittarius Bow has a stronger Mercury-based unleash, it is only available in Crossbone Isle, which can only be accessed after the player has defeated the final boss. Thus, the Masamune is likely to see far more time than the Sagittarius Bow. Once the final boss is defeated however, the Sagittarius Bow becomes the best possible replacement, as it is more easily acquirable than the Tisiphone Edge and matches up better with Amiti's elemental alignment.

Trivia
In the original Golden Sun, a weapon hidden in the game's code named "Masamune" can be seen and found either through or in the Debug Rooms. It is a Long Sword with a unique and different graphic not officially seen in either game, has 135 Atk, and has no Unleash effect. If transferred into The Lost Age, it becomes the Fire Brand.

Cultural references
Okazaki Masamune, who lived in the 13th and 14th centuries, is regarded as the greatest swordsmith of Japanese history. In addition to his extraordinary worksmanship, he is typically regarded as the exemplar of the true warrior who does not kill needlessly, in contrast to Murasame's alleged bloodthirst.