Sol Blade

The Sol Blade is a Long Sword-class Artifact weapon found in Golden Sun: The Lost Age and Golden Sun: Dark Dawn. It is the "ultimate weapon" of each game it appears in, having the second-highest base Attack of all weapons in the series and extremely powerful Unleashes, and can only be equipped by the lead Venus Adepts - Isaac and Felix in The Lost Age and Matthew in Dark Dawn. For all its power, in each games it is very easy to find - in The Lost Age it is found in one quick puzzle in Mars Lighthouse, whereas in Dark Dawn it is automatically acquired in the final stages of Apollo Sanctum shortly before the final boss battles.

Basic description by game
The Sol Blade increases its wielder's base Attack by 200 points, which is the second-highest attack rating increase of any piece of equipment in The Lost Age - the only weapon with a higher attack rating increase is the Darksword, with 210 attack. In The Lost Age, it is an Artifact weapon that is found in a treasure chest deep in Mars Lighthouse, as a rather easy reward for solving a platform-based ice puzzle shortly before a boss battle with the Flame Dragons. It can be sold for 23400 coins, and can subsequently be bought back for 31200 coins. Unlike other Long Swords, this can only be equipped by Isaac and Felix, leaving out Garet and Piers.

Its Unleash effect, Megiddo (Harumagedon/Armageddon in the Japanese version), deals a Venus-aligned attack equal to the user's normal physical attack rating, and all resultant damage is multiplied by 3. Megiddo appears as the user slowly jumping through a red backdrop as the sword glows and a Sun-like sphere of burning plasma appears from the top of the screen, followed by the user swinging the sword and the sphere crashing down onto the target and turning the screen white.

In Dark Dawn, the Sol Blade is found in the final area of the game at Apollo Sanctum; after using the Colored Orbs on their respective pedestals and the lens starts to get set up, players are to proceed south of the topmost part of the screen to where the Sol Blade is in the ground, and Matthew will draw it out of the ground and obtain it, which will activate another part of the area's puzzle. The Sol Blade is especially unique among the game's weapons because it has a utility Use effect in the field as well: it doubles as a key that opens special locked doors like the one now at the bottom part of the screen. Following the final dungeon, players may return to Otka Island and Burning Island Cave and open doors with the Sol Blade to access the Ancient Devil and Ogre Titan optional boss battles.

The Sol Blade and its Megiddo unleash are the same as in The Lost Age, with Matthew being the only one that can wield it, but now Megiddo is the fourth and final of the several Unleashes the sword may randomly choose from when an Unleash with the Sol Blade is triggered. Like with all other weapons, several other Unleashes have been added: the first Unleash is Centurion, otherwise only found as the strongest Unleash of the Phaeton's Blade and Levatine, which is a Jupiter-aligned attack equal to the user's normal physical attack multiplied by 2.4, and there is a chance that the resultant attack will ignore 50% of the target's Defense. The second Unleash is Radiant Fire, otherwise only found as the exclusive theme Unleash of the Levatine, which is a Mars-aligned attack equal to the user's normal physical attack with 66 damage points added to the result, and each foe adjacent to the target is also hit - so that up to 3 foes can be hit. Each hit foe also has a chance to have 50% of their Defense be ignored by the hit. Its third Unleash is Purgatory, otherwise only found as the theme Unleash of the Fire Brand, which is a Mars-aligned attack equal to the user's normal physical attack with 67 damage points added to the result and a chance to inflict Sleep.

The Lost Age
The Sol Blade is the best weapon in The Lost Age. Its 200 Attack is only beaten out by a Darksword's 210 Attack, but as that weapon's Venus-based Unleash doesn't multiply damage, it can't compare to the Sol Blade's overall damage output in the long run. Sol Blade's only competition among other weapons are Excalibur and Tisiphone Edge, and to a lesser extent the Masamune, all weapons that have Unleash effects with the potential to multiply the damage done. But while Excalibur and Tisiphone Edge may triple the damage done, the Sol Blade's Megiddo always scores triple damage. The Sol Blade is also conveniently located in a chest, rather than as a random drop or forge, meaning that any players that make it to the end of the game will most likely have this whether they try to get Excalibur or Tisiphone Edge at all.

It's possible to arrange equipment on an Adept wielding the Sol Blade to raise his Unleash chance so high that he will unleash a Megiddo every single time he uses a normal physical attack. Like most other weapons in the GBA games, the Sol Blade's Unleash chance for Megiddo has the base rate of 35%. The Venus Adept can don a pair of Riot Gloves to add 20% to the Unleash rate (as well as augment Attack power somewhat), equip the Valkyrie Mail for another 20%, a Mythril Helm forged from a Mythril Silver for 12% more, and finally Hyper Boots won at the Lucky Wheels in Contigo, to raise it 12% more to make for an Adept with a 99% chance of Unleashing Megiddo every time he attacks. This character becomes a complete powerhouse—able to help kill the Doom Dragon in much less time, fell most common enemies in one hit, and easily destroy the Star Magician's Ball minions. (Incidentally, if the Ninja Sandals programmed into this game were made available, its 15% Unleash rating boost, 3% superior over the Hyper Boots, would make the Unleash rate breach 100%.)

But reaching 99% requires Minos Knights in the Yampi Desert Cave to drop the very rare Riot Gloves, and the blacksmith in Yallam to randomly forge hard-to-get Mythril Silver into a Mythril Helm. If the player considers these two items implausible to get, the player may instead use the Warrior's Helm in the Mythril Helm's place. It has less defense, but it still sports a 10% additional Unleash chance, and also grants a small increase in Venus power, which complements Megiddo's damage output a little. As for a substitute for the Riot Gloves, the only equipment that can suffice here is the Aegis Shield won at the Lucky Medal Fountain in Lemuria. It has only a 10% additional Unleash, half as much as the Riot Gloves' 20%, and it lacks the Attack boost. A Sol-Blade-wielding Adept with the Warrior's Helm, Valkyrie Mail, Aegis Shield, and Hyper Boots will at least achieve an Unleash rate of 87%.

Dark Dawn
The Sol Blade in Dark Dawn is still the best weapon overall, but the additional lesser unleashes that it carries in addition to Megiddo end up making it a less reliably super-powered weapon. Its first unleash, Centurion, ends up close to the power of Megiddo because it has its own high damage multiplier and the chance to deal further damage by ignoring part of the target's Defense, but its Jupiter power is misaligned with Matthew's. Radiant Fire is less powerful because it only adds damage to the result (66), but it at least has a different kind of use by hitting multiple enemies at a time. Easily the poorest Unleash in Sol Blade's repertoire is Purgatory, which adds the same amount of damage as Radiant Fire and only adds a chance to inflict the Sleep status condition—no chance to ignore enemy Defense, and no capacity to hit multiple foes at a time. Notably, unlike Megiddo, all three of these earlier Unleashes have elemental affinities that do not match Matthew's Venus power rating.

Like in The Lost Age, equipment exists that together raise Matthew's Unleash rate with the Sol Blade for nearly guaranteed unleashes: the Warrior's Helm found in Teppe Ruins, the Valkyrie Mail found in Apollo Ascent, the Aegis Shield found in Warrior's Hill, the Ninja Sandals found through the sidequest involving the Grandmother's Gift and Grandchild's Gift, and the Lord Sun's Ring found in Tonfon. But unlike in The Lost Age, none of these items require random drops or forging, meaning that it's easier to max out the Unleash rate. This does not, however, have any effect on which Unleash is chosen.

There are a couple strategies to consider when bringing the Sol Blade to the final battles: Setting Mars Djinn on Matthew to put him in the Chaos Lord class is ideal because Chaos Lord has a more powerful attack statistic than the Slayer class to begin with, and the Chaos Lord's other stats are either at the same level or higher than the Slayer class as well. Even though there are less Venus Djinn set to increase Matthew's Venus Power and therefore the resultant damage of Megiddo, the sharply increased Attack rating will more than make up for that deficiency anyway, increasing the damage of Megiddo and the other three unleashes as well. The two Mars-based unleashes will be especially improved, in relative terms, because of the increase to Mars Power that the set Mars Djinn themselves will also provide.

The other, more subtle strategy concerns a way to manipulate what the weapon will unleash: Like with any newly acquired weapon, Matthew would not be able to use any of its Unleashes until he has attacked plenty of enemies like the Tua Warriors at the Apollo Lens with it, unless he has already trained a lot in earlier Long Swords like the Fire Brand, in which case he may already know the first Unleash or two. However, since the first Unleash, Centurion, is clearly superior to the two Mars Unleashes that follow, then if Matthew knows only Centurion on the Sol Blade, have him use Psynergy to battle until the final battles so that his Sol Blade weapon mastery is kept from rising further. This way, he can then unleash a reliably powerful Centurion each time he attacks, and this will work for a while until Radiant Fire is learned.

Trivia

 * The Sol Blade actually exists in the code for the original Golden Sun, including its item icon and its status as a Long Sword-class weapon artifact. During development the Sol Blade was apparently originally planned to be the game's "ultimate weapon", but was reserved for an appearance in the GBA follow-up and remains normally inaccessible to players of the first game without a hacking device that either grants the weapon directly or grants access to the game's Debug Room, where it can also be acquired. The Sol Blade in this incarnation has "???" as its item description and has no Unleash coded for it; it is merely a weapon artifact that increases base attack by 138, which is technically the highest attack rating increase in the original Golden Sun more than the "proper" recipient of that honor, the Gaia Blade's 135 Attack power. If this version of the Sol Blade is present in the party's inventory when the Golden Sun game file is saved as a Clear Data file, and the file data is transferred over to The Lost Age, the Sol Blade becomes its properly working, full-powered, Megiddo-unleashing self.