Ninja Blade

The Ninja Blade (Shinobi Katana in Japan) is a Light Blade-class Artifact weapon found throughout the Golden Sun series.

Basic description by game
In all its appearances, a Ninja Blade increases the wielder's attack by 94 points. It can be bought from vendors for 8800 coins and sold for 6600 coins.

In the original Golden Sun it is first available in Lunpa, and can be equipped by Isaac, Garet, and Ivan. In Golden Sun: The Lost Age, it is first available in Izumo, and can be equipped by Felix, Jenna, and Piers. In the first two games, the Ninja Blade's sole Unleashed power is Cyclone Slash ("Cyclone Attack" in the item screen, which was fixed back to "Cyclone Slash" for The Lost Age; Resist Slash in Japan). Cyclone Slash converts all damage to Jupiter damage and attacks with an additional 38 attack points. It may also lower the target's resistances by 40 (this effect can stack twice). Visually, Cyclone Slash appears as a light violet whirlwind that blasts the target into the air when the blade hits.

In Golden Sun: Dark Dawn, the Ninja Blade is first available in the town of Yamata, and can be equipped by Matthew, Tyrell, Karis, Amiti, Eoleo, and Himi. Due to revisions to the unleash system, the Ninja Blade has gained two additional unleashes. The first Unleash learned is Critical Move, a non-elemental physical attack that multiplies damage by 1.4. The second Unleash is Cyclone Slash, which is carried over from the first two games. Uniquely, this makes the Ninja Blade one of the few artifact weapons that does not have its former signature Unleash as the last Unleash learned. Instead, the final Unleash is Zenith Strike, a physical attack that converts all damage to Jupiter damage and attacks with an additional 59 points.

Analysis
This generally becomes Ivan's best weapon for when it can first be  found, which is after completing the optional Lunpa  Fortress and the shops in Lunpa reopen for business. The blade's Unleash has its power increased if its wielder has a high Jupiter power rating, so Ivan, who has naturally high Jupiter Power, can do respectable damage with the Unleash to enemies that have low Jupiter resistance. Ultimately, it becomes a good placeholder for until Ivan acquires the best Jupiter-element weapon he can equip in Lalivero, the Swift Sword. The Ninja Blade is not as useful in The Lost Age, though, because the main Jupiter Adept in your party, Sheba, cannot equip Light Blades.

In Dark Dawn, the Ninja Blade overall is given a slight improvement due to the addition of Zenith Strike, which adds more damage than does Cyclone Slash. However, it is not likely to see much use, since the player will have already obtained the Jupiter-based pure element weapons, the Sylph Rapier and the Yew Bow, which are both stronger than the Ninja Blade. Also, the player will already have access to more powerful forged weapons. If the Ninja Blade is used, it will most likely be a short term placeholder.