Gaia Blade

The Gaia Blade (ガイアのつるぎ, Gaia no tsurugi^?, lit. Sword of Gaia) is a Long Sword-class Artifact weapon findable in Golden Sun, transferable to Golden Sun: The Lost Age, and findable in Golden Sun: Dark Dawn. Its parameters clearly position it as the first game's "ultimate weapon" for Isaac.

In Golden Sun

Gaia Blade (GBA)
Visual effect of Titan Blade
In-Game Description
"Long Sword: Unleashes Titan Blade" (GS) (TLA)
Trade Info
Weapon class	Long Sword
Buy value	17000
Sell value	12750
Artifact?	Yes
Statistic Boosts
Attack Boost	135
Elemental Power Boosts	20
Resistance Boosts	20
Unleash effect
Effect name	Titan Blade
Extra damage	70
Acquisition
• Chest in Venus Lighthouse's main portion (GS)

In Golden Sun, equipping the Gaia Blade adds 20 points to the holder's Venus Power and Venus Resistance ratings. This complements how it is one of a handful of weapons that passively treats standard physical attacks dealt with it as aligned with an element, in this case the Venus element. As a result, the damage dealt is increased by the holder's Venus Power rating and similarly decreased by the target's Venus Resistance rating.

In the first game, the Gaia Blade is rather easily found in one of the various treasure chests the party passes by while progressing through the final storyline dungeon, Venus Lighthouse, at around the lower-right corner of a room with rushing sand rivers. As a Long Sword-class weapon, only the "warrior-style" Adepts Isaac and Garet can hold it, and so can Felix and Piers in Golden Sun: The Lost Age if the password system has been used to transfer the first party's inventory to the second game. There is no way to acquire the Gaia Blade in The Lost Age otherwise.

The Gaia Blade's Unleash effect, unleashed with a default probability of 35% like almost all other cases, is Titan Blade (タイタニック, Taitanikku^?, lit. Titanic), which is a Venus-aligned physical attack that adds an impressive 70 points of bonus damage after all other calculations. The Titan Blade sequence visually appears as the wielder summoning and remotely driving a colossal yellow sword straight into the target's position, and a mass of bouncing yellow energy orbs spew from the ground before the sword detonates in a large explosion of purple energy.

In Golden Sun, the Gaia Blade is clearly the best weapon for the Venus Adept Isaac to wield because his naturally high Venus power rating and high Attack stat, compared to Garet, stack up with the weapon's own high Attack stat increase and fair Venus Power increase to shape the damage of innately Venus-aligned attacks dealt with the Gaia Blade. Furthermore, Titan Blade adds the highest bonus damage value of all weapon unleashes in the first game, so whenever Isaac happens to unleash it with one of his standard attack commands, it amounts to a larger damage bonus than Isaac casting the similar Ragnarok Psynergy while holding the Gaia Blade. This is not to mention that any damaging Venus Psynergy like Mother Gaia and restorative Venus Psynergy like Potent Cure will also have a stronger effect while Isaac is holding the weapon.

While the first game's more limited list of equippable items leaves Isaac with fewer means of raising his chance to Unleash with weapons in general, it is still possible to equip Hyper Boots from Tolbi's Lucky Medal Fountain to add 12% to the chance, and to equip the Warrior's Helm from Lalivero to add 10% more to the chance (and add 10 more Venus Power as well), to give him a 57% probability of producing Titan Blade with each attack. While it might be preferable to equip more defensive body armor like Dragon Scales on him, it is feasible to have a Spiked Armor somewhat rarely drop from a wild Chimera Mage in Babi Lighthouse and beyond. This armor adds somewhat less Defense but adds 10 more Attack points and improves Unleash rates by a further 6%, making it possible for Isaac to Unleash Titan Blade with a maximum probability of 63%.

Even with this particular gear setup, a player wishing for more reliability than having to rely on proccing a very powerful Unleash effect that might only happen a little over half the time might consider casting Ragnarok instead; this produces a Venus-aligned physical attack that lies at the "midpoint" between the damage output of a standard attack with the Gaia Blade and an unleash of its Titan Blade effect.

The matter of body armor aside, the Warrior's Helm and Hyper Boots are clearly Isaac's best-in-slot gear for those two gear slots on account of how well they synergize with the Gaia Blade. As for his hand slot, the War Gloves bought at Lunpa are preferable for their significant Attack rating increase compared to what can be judged as a minuscule 5-point Venus Power increase coming from the Spirit Gloves found in Kalay Tunnel after rescuing Master Hammet.

Since any instance of Golden Sun: The Lost Age being played with a Gold-level password from the first game will most likely include the Gaia Blade in the inventory of the first game's party, it will be an excellent placeholder weapon for Isaac to wield for a potentially long time. Despite its 135-point Attack increase falling behind weapons Felix's party may have acquired by that point, like Hestia Blades from Lemuria's own Lucky Medal Fountain and the Phaeton's Blade from Jupiter Lighthouse, the Gaia Blade's Titan Blade unleash still features a very high bonus damage value, and the weapon's Venus power increase benefits Isaac's Psynergy in its own ways. This prevents the weapon from being significantly worse for Isaac to wield than the three higher-Attack Venus-themed weapons that can be forged from Golem Cores: Huge Sword, Gaia's Axe, and Tungsten Mace, the former two of which are also innately Venus-aligned.

In Golden Sun: Dark Dawn

Gaia Blade (DD)
The DS model of the Gaia Blade
In-Game Description
"Weapon: Long Sword (Boosts Earth Power)" (DD)
Trade Info
Weapon class	Long Sword (Matthew only)
Buy value	17000
Sell value	12750
Artifact?	Yes
Statistic Boosts
Attack Boost	168
Elemental Power Boosts	20
Resistance Boosts	20
First Unleash effect
Effect name	Power Charge
Extra damage	x1.4
Side effect	May drop target's defense by 25%
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	Titan Blade
Extra damage	70
Acquisition
• Chest in Yamata Ruins (DD)

For its appearance in Golden Sun: Dark Dawn, the Gaia Blade is one of very few items to have adjusted base parameters between games, having gained 33 more base Attack to make for a new total of 168. In another odd detail, only the leading Venus Adept Matthew can equip it in this game despite Tyrell also being capable of equipping long swords. The Gaia Blade is hidden deep within the Yamata Ruins very late in the game, in a room that players can easily miss because it requires them to make use of both the plot-important Yellow Orb they just acquired and the Utility Psynergy Search.

Like all other weapons in the game, multiple alternative choices for randomly chosen Unleash effects can be produced when the Unleash proc chance check is passed, depending on how much weapon mastery Matthew has built up in it specifically. Its four total unleash effects are unlocked in this order: Power Charge (パワーチャージ, Power Charge^?), a Mars-aligned attack that increases the resulting damage by 40% and carries a 70% default chance to lower the target's Defense stat by 25%; Spiral Assault (スパイラルアタック, Spiral Attack^?), a Jupiter-aligned attack that increases the damage output by 30% and hits up to two other adjacent targets for lesser damage; Sky Diver (スカイダイバー, Skydiver^?), another Jupiter-aligned attack that adds 65 bonus damage and carries a 40% default chance to Stun the target; and Titan Blade from before, which is unchanged.

In Dark Dawn, the "earliest" opportunity to obtain the Gaia Blade lies at a point in the third act of the game where the only other task that needs to be finished before beginning the final dungeon is to find all the pieces of the Umbra Gear scattered across the world map. By that point, despite the attack rating increase it has been blessed with since the GBA duology, it is likely that Matthew will already be equipped with something even more powerful. These include weapons like Levatine, Phaeton's Blade, Excalibur, and Masamune, the last of which is ironically found in Yamata Ruins during a much earlier visit to the dungeon. None of this is to mention that the final dungeon itself will automatically grant Matthew his ultimate weapon, the Sol Blade, which is vastly superior.

That said, the fact the Gaia Blade retains its Venus power boost improves several choice Venus Psynergies that Matthew can cast. Taken together with the Venus power boost offered by the Warrior's Helm much earlier in Teppe Ruins and the usable multi-elemental power boost of the Planet Armor from Port Rago, the Gaia Blade can be a good placeholder if not too many of the other powerful weapons that can be acquired before the endgame have been found yet.

Like with many other weapons, the Gaia Blade randomly choosing between Titan Blade and three other, "lesser" Unleash effects the way all other weapons do in this game makes it less reliable to score consistently high damage with. This is especially true in this weapon's case because all three of the additional Unleash effects that must be learned before Titan Blade can be unlocked are aligned with elements other than Venus, which means none of them benefit from the built-in Venus power boost. Power Charge, for example, is Mars-aligned, improves resulting damage by a modest 40%, and potentially lowers some of the target's Defense stat, making it perhaps the weakest of Gaia Blade's unleash repertoire.

Its Spiral Assault unleash effect, though aligned with Jupiter and using an even less impactful 30% damage multiplier, occasionally amounts to a useful effect coming from the Gaia Blade because it is the weapon's only method of hitting multiple targets at a time. The Sky Diver unleash is also Jupiter-aligned, but it adds almost as much bonus damage as Titan's Blade and additionally carries a stun chance, perhaps making it roughly as useful in practice.

It should be noted that increasing Matthew's Attack rating through leveling up, equipping other categories of gear that give bonus Attack, changing to high-Attack classes like the Brute class series, and getting Attack buffs from Psynergies like Impact and Weapon Grace does more to improve the proportional damage output of all these Unleashes than in the last game. This is because monster defense ratings are significantly higher on average and thus work to subtract higher values from the physical damage dealt to them, so attack rating buffs and Unleashes that add lots of bonus damage after the fact can easily stack up and change a 100-damage strike late in the game to 250 damage or so. Once that threshold is cleared, however, if Matthew's attack rating is brought high enough, even the weaker percentage-based multipliers of Power Charge and Spiral Assault should result in strikes that deal close to the amount of damage as the additive-in-nature Sky Diver and Titan Blade.

The Ninja class series can work especially well with this weapon because its Master class stage features the same superlative Attack rating modifier as the Chaos Lord while also having several Mars Djinn and Jupiter Djinn supplying elemental power ratings to Matthew, which further enhances the damage output of the weapon's Mars- and Jupiter-aligned Unleashes.

Of course, by this point, any of the aforementioned alternative weapons will be capable of much more powerful unleashes in the hands of a high-Attack Matthew because of how much higher their damage multipliers can reach. And since the Gaia Blade cannot be handed down to Tyrell or anyone else once a weapon capable of an unleash like Centurion or Rising Dragon is in Matthew's hands, it will likely be sold off unceremoniously.

Gallery of Dark Dawn unleashes

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  Power Charge

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  Spiral Assault

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  Sky Diver

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  Titan Blade