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Xenoblade Chronicles 2 is a huge game with an astonishing amount of Blades for players to acquire, upgrade, and wield in battle. These come in the elements Fire, Water, Ice, Wind, Earth, Electric, Light, and Dark. While there are plenty of available Blades for some elements, others have only a few options available to the player, such as Light.
In Xenoblade Chronicles 2, there was initially only one Light element Blade other than Mythra that could be obtained (Not counting Poppi with a Light Core), making Light the rarest element in the game. While DLC and updates did change this with the addition of Blades like Poppibuster and Corvin, the hidden Light Blade from the initial release remains one of the stronger available Blades in the entire game, and this guide will explain where to find her.
KOS-MOS, Who is She?
KOS-MOS is a Light element Ether Cannon Blade with a fantastic array of abilities, but she's also a cameo from a previous Xeno-game, Xenosaga. Without going too far off track talking about her history, she's a powerful Combat Android created to fight the main enemy of the Xenosaga series, known as "Gnosis." In her home series, she summons various weapons, mainly firearms, to fight, which is reflected in her Ether Cannon Blade weapon.
Her Battle Skills are Phase Transition Tech, Hyperclock, and Encephalon. Phase Transition Tech will Nullify Enemy Defenses while boosting her Special damage by 70% (100% when fully upgraded). Hyperclock boosts her damage dealt by 60% (100% when fully upgraded) and reduces her damage taken by 10% (30% when fully upgraded). Finally, Encephalon reduces Aggro buildup from her attacks by 25% (40% when fully upgraded)
Her Blade Arts are Recharge Boost, Arts Plus, and Critical Up, allowing her to recharge arts faster, increase the power of Driver Arts, and improve the critical hit rate. Her field skills are Light Mastery, Lockpicking, and Mental Arithmetic, allowing her to help players crack locks and make use of the Light Element to brighten up dark areas in the world. Mental Arithmetic is her exclusive Field Skill and is used both in her Blade Quest and to speed up certain Mercenary Missions.
Her Level 1 Blade Special is R-Blade, which has a 25% boost to Critical Damage (85% when fully upgraded). Her Level 2 Blade Special, H-Effect R, heals the party for 30% of the damage dealt (50% when fully upgraded). Her Level 3 Blade Special is F-G-Shot, which has a 60% chance of dealing a Guard-Annulling Attack (100% when fully upgraded). Finally, her Level 4 Blade Special, X-Buster, has a 100% chance of dealing a Guard-Annulling Attack and has a 60% boost to Critical Damage.
How to Get KOS-MOS
Acquiring KOS-MOS is predominantly a result of random chance, though there are several methods to boost the probability of getting her when using Core Crystals. By default, assuming a normal Core Crystal and no modifiers, there is a 0.1% chance of getting KOS-MOS when using a Core Crystal.
Using a Legendary Core Crystal gives a 3x chance, maxing out the character's luck (999 Luck) will give a 1.36x boost, and getting the Justice Value to 15 will give a 1.75x boost. Assuming the player has also already acquired every other Rare Blade, this means the odds of getting KOS-MOS should be around 71.9% when using 200 Legendary Core Crystals. This is no easy feat, but it does offer the best chance of acquiring KOS-MOS. This assumes the player isn't in NG+ yet, since NG+ adds new rare blades beyond those accessible in the first playthrough.
Players using the same methods above but with only 7 Justice will still have roughly a 63% chance, so it's possible to attempt this with less Justice and still achieve the same result, though the probability is a little lower. When it comes to prioritizing different elements to improve odds, the quality of the Core Crystal is the first most important part of the equation, followed by the idea value (Justice in this case).
- Xenoblade Chronicles 2 is available for Nintendo Switch.
