Basic Description by Game
It is sold in armor vendors at Tolbi in Golden Sun, at Apojii Islands in Golden Sun: The Lost Age, and at Belinsk, Port Rago, and Champa Camp In Golden Sun: Dark Dawn. In Dark Dawn, one Armored Shell can also be found in a chest in Craggy Peak Ruins. Being an Armor-class piece of body protection, an Armored Shell can be equipped on warrior-style Adepts, namely Isaac and Garet in the first game, Felix and Piers in the second, and Matthew, Tyrell, and Eoleo in the third.
In Golden Sun, Armored Shells are generally not necessary, as the player can win more useful armor in the nearby Tolbi Spring. The Lucky Medal minigame freely dispenses all sorts of equipment that is very powerful and useful at that point in the game, with one of the best prizes being the armor Artifact Spirit Armor. This armor, with 32 Defense and adds 15 to all four elemental resistances for the equipped Adept, is so good it is actually better to equip than the Armored Shell's two later commonly-sold counterparts, the Plate Mail and the Steel Armor. Redeeming all your Lucky Medals at Tolbi Spring for equipment like Spirit Armors before even stepping into the shop at Tolbi is how a "perfect" game of Golden Sun would likely be played.
In Golden Sun: The Lost Age, Armored Shells can first be bought in Apojii Islands, meaning they are available to buy as soon as you get the Lemurian Ship to sail the Great Eastern Sea with. It's true an Armored Shell is a significant-enough defense boost over a Psynergy Armor a warrior Adept might be wearing to consider replacing that with this, but the next level of common armor, the Plate Mail, also becomes available for buy at a shop in a Great Eastern Sea settlement (Champa, namely) at the same time as the Armored Shell.
In Golden Sun: Dark Dawn, when the first Armored Shell is found, Ixion Mail is already available, and probably more useful because of its bonuses to its wearer's resistances. Furthermore, the even better Spiked Armor can be found in the same dungeon as the Armored Shell, so between these two, there is little reason to use it. By the time Armored Shells become available in shops, they are completely outclassed by the Plate Mails that become available at the same time, so there is absolutely no reason to buy them.
|Body Armor featured in Golden Sun|
|Leather Armor • Psynergy Armor • Chain Mail • Armored Shell • Spirit Armor • Plate Mail • Steel Armor • Spiked Armor • Asura's Armor • Dragon Scales • Demon Mail|
|Body Armor featured in Golden Sun: The Lost Age|
|Leather Armor • Psynergy Armor • Ixion Mail • Chain Mail • Armored Shell • Plate Mail • Planet Armor • Steel Armor • Phantasmal Mail • Erebus Armor • Dragon Mail • Chronos Mail • Stealth Armor • Xylion Armor • Valkyrie Mail|
|Body Armor featured in Golden Sun: Dark Dawn|
|Leather Armor • Psynergy Armor • Ixion Mail • Chain Mail • Armored Shell • Plate Mail • Planet Armor • Steel Armor • Chronos Mail • Spiked Armor • Asura's Armor • Dragon Mail • Demon Mail • Xylion Armor • Valkyrie Mail|