Prism Slime and Mushteshir Guide in Genshin Impact (Frost Moon)

TL;DR

• Prism Slime and Mushteshir are the two new Frost Moon Local Legends added in Genshin Impact 6.7.
• Both bosses live inside Ungien’s Circle on the Frost Moon, the lunar part of Nod-Krai.
• You need to clear the Moon Gazing world quest chain before either boss shows up.
• Prism Slime is south of the Circle near Moon Lake and steals your active character’s energy.
• Mushteshir is northwest of the Circle and is completely immune to Hydro.
• Beating both bosses and clearing all six achievements gets you 120 Primogems.

What Are Prism Slime and Mushteshir in Genshin Impact

Prism Slime and Mushteshir are two brand-new Local Legends added with the Luna VIII update, patch 6.7. Local Legends are basically super-charged versions of enemies you already know, and clearing one pays out through the Nod-Krai Adventurers’ Guild instead of dropping loot on the spot.

Both of these bosses are tucked inside Ungien’s Circle, a key area on the Frost Moon. If you haven’t unlocked the Frost Moon surface yet, none of this will matter, since neither boss spawns until you’re far enough into the Moon Gazing world quest chain.

How to Unlock Prism Slime and Mushteshir

Before you go hunting, finish the Pioneer Quest and keep pushing through Moon Gazing until the Frost Moon surface opens up. Once that’s done, Ungien’s Circle becomes fully explorable and both Local Legends become trackable on your map.

Prism Slime Location and Fight Guide

Prism Slime Location and Fight Guide

Prism Slime sits at the southern edge of Ungien’s Circle, right on the cliff above Moon Lake. Here’s the fastest way to reach it.

• Teleport to Ungien’s Circle’s southern Transit Station.
• Head toward the south-western Lunar Highlands waypoint.
• Hop onto the southern Fast Transit Lane and keep an eye on your destination marker.
• When you reach the marker, jump out and glide down to unlock the waypoint.
• From there, walk west. You’ll spot a giant slime shimmering with every element hanging over the drop.

Prism Slime’s whole gimmick is stealing energy from whichever character you have active and then going immune to that element. This means a mono-element team falls apart fast here, so bring a mixed squad with a strong burst DPS instead.

Prism Slime Achievements

• Defeat Local Legend: Prism Slime — 20 Primogems, 3 Slime Concentrate
• Beat it before the third light-gathering phase — 20 Primogems, 3 Guide to Moonlight
• Defeat it before its first swelling phase, with no more than 2 energy absorption attempts — 20 Primogems, 25,000 Mora

All three achievements can be done in one clean run. Bring a team that can burst it down fast, since a well-timed Elemental Burst chain is the easiest way to end the fight before Prism Slime gets a chance to absorb energy a third time.

Mushteshir Location and Fight Guide

Mushteshir is hiding in the Kalag Guarding Grounds, in the northwest section of Ungien’s Circle. Here’s how to get there and trigger the fight.

• Fast travel to the north-western waypoint in Ungien’s Circle.
• Head north-east until you spot an entrance.
• Push through the crack in the wall into the north-western passage.
• Find the mechanism inside and interact with it.
• Clear the intermediate wave, then the advanced wave of automatons.
• Interact with the mechanism a third time to trigger the ultimate validation, which summons Mushteshir.

Mushteshir is a humanoid automaton, and it’s completely immune to Hydro, so leave your Hydro units at home for this one. Below 50 percent HP, it triggers a Suppression Field: a purple sphere that slows you down, cuts skill recharge by 30 percent, and spawns four flying detection devices. While those devices are alive, Mushteshir gets roughly 70 percent resistance to all elements and slowly heals itself back up.

The fix is simple: shoot the devices down fast. Ranged characters with good tracking hits work best here, and bringing Stellar-Conduct or Super-Conduct reaction teams helps chip through Mushteshir’s defenses once the field goes up.

Mushteshir Achievements

• Defeat Local Legend: Mushteshir — 20 Primogems, 3 Unblemished Lunar Iron
• Defeat Mushteshir while it’s paralyzed — 20 Primogems, 3 Guide to Conflict
• Paralyze it by destroying all 4 detection devices during the first Suppression Field — 20 Primogems, 25,000 Mora

You can knock out all three Mushteshir achievements in a single fight. Focus the detection devices the moment the Suppression Field goes up, and once Mushteshir is paralyzed, dump your strongest burst on it before the field comes back.

Total Rewards for Both Local Legends

Clear all six achievements between Prism Slime and Mushteshir, and you’ll walk away with 120 Primogems total, plus Mora, talent materials, and a handful of Slime and Iron drops. Keep in mind rewards aren’t automatic. After beating either boss, head to the Nod-Krai Adventurers’ Guild and claim the reward tied to that Local Legend manually.

Tips Before You Fight Both Bosses

• Bring a mixed-element team for Prism Slime so it can’t go immune to everything you throw at it.
• Skip Hydro units entirely for Mushteshir since it just won’t work.
• Use ranged characters to snipe Mushteshir’s detection devices the instant the Suppression Field appears.
• If Mushteshir won’t spawn, make sure you’ve actually cleared both automaton waves at the mechanism first.
• Both fights reward a fast burst rotation more than a slow, sustained one.

Where to Play Genshin Impact

You can jump into the Frost Moon update on HoYoverse’s official site, or grab the game on Google Play, the App Store, PlayStation, Epic Games Store, or Xbox.

Frequently Asked Questions

For more Frost Moon boss guides, check out our Azhdaha Trounce Challenge guide and our Childe Trounce Challenge guide. If you’re building a ranged unit for these fights, our Chasca character guide and Wriothesley character guide are worth a look. You can also check our Facility Interior exploration guide for more Nod-Krai region content.