List of Lightning Returns : Final Fantasy XIII shields In " " , Lightning has a variety of shields in her arsenal . Their common traits are raising maximum HP and status resistance . Shields can be upgraded from the after defeating the final boss . They can be upgraded at forges for a small fee and various materials that can be bought at the , or obtained from defeated enemies . The best materials are only available as enemy drops . It ' s not possible to upgrade shields to their maximum values , because each item can only be upgraded a set number of times . One can max - out a couple of stats at most , but never all of the possible parameters . Upgrading a shield the first time earns the achievement . Upgrading a shield thirty times earns the achievement . One can also downgrade shields , but this will not refund the materials used to upgrade them although it does " refund " the number of upgrades . Downgrading can therefore be considered as the backup plan in case one upgrades a shield the wrong way . Defense formulas . Guard Efficiency . Guard Efficiency is a percent damage reduction multiplied by the Physical and Magic Resistance of the used ability . For example , with 100 damage the formula for receiving it using the example above would be : Instead of receiving 100 damage , Lightning would receive 64 damage . Guard Defense . Guard Defense is a flat damage reduction which is calculated as a subtraction from the multiplication of incoming damage , ability ' s percent damage reduction , and a shield ' s Guard Efficiency . Using the example above , the damage calculation for Guard Defense with 50 points would be : Shields . Well - balanced shields . Well - balanced shields generally boost HP and Guard Defense . Large shields . Large shields boost HP and Guard Defense , but come with the drawback of reducing ATB Speed . They focus on providing massive amounts of HP and include the auto - ability which increases Keep to reduce enemy interruption of abilities . Tactical shields . Tactical shields boost HP , ATB Speed , and Guard Defense . Ensorcelled shields . Ensorcelled shields boost ATB Speed , Guard Defense , and Magic . Light shields . Light shields boost HP and ATB Speed . They focus on ATB Speed and include the auto - ability , which increases damage resistance by a certain percent while actively guarding . Valuable shields . Valuable shields boost HP and improve elemental resistance while guarding , but they reduce ATB Speed . They include two , which strengthen elemental resistances . Crest shields . Crest shields boost HP and Guard Defense and have varying effects on ATB Speed . Other shields . The following shields are available either from having save data from previous entries of " Lightning Saga " games or from downloadable content . Many of them have traits which are reminiscent of one of the seven types from above . Gauntlets . Gauntlets are similar to ensorcelled shields in that they raise ATB Speed and Guard Defense by a fair amount , but instead of Magic they augment Strength . They are best suited for Schema which rely on physical abilities . Etymology . The large shields are inspired by Arthurian legends : Prytwen was the name of King Arthur ' s ship , Pendragon was King Arthur ' s surname , Dame du Lac , is French for Lady of the Lake , from whom he received Excalibur ; Guard of Avalon , the paradise Arthur went to upon his death , and Knight ' s Pledge refer to the Knights of the Round Table .