Nuxlar-UmbralMithrix icon


The Umbral King of Nothing uses shadows and clones to overwhelm his enemies.

Last updated 9 hours ago
Total downloads 7141
Total rating 2 
Categories Server-side Mods Survivors of the Void
Dependency string Nuxlar-UmbralMithrix-1.4.1
Dependants 1 other mod depends on this mod

This mod requires the following mods to function

bbepis-BepInExPack-5.4.2102 icon

Unified BepInEx all-in-one modding pack - plugin framework, detour library

Preferred version: 5.4.2102
tristanmcpherson-R2API-4.4.1 icon

A modding API for Risk of Rain 2

Preferred version: 4.4.1
Rune580-Risk_Of_Options-2.5.3 icon

A convenient API for adding BepInEx ConfigEntry's to a option menu

Preferred version: 2.5.3


Umbral Mithrix

Accursed Mithrix reworked variant with clones and new Phase 4 (For more info on the base mod

Blacklisted Items (from mithy and doppels): Tesla, Nkuhanas, Empathy, Drone Parts, Razorwire

Phase info:

  • Phase 1 Mithrix now jumps on you for a Crushing Leap, get in the air. Bash and Slam spawn a deteriorating glass clone with full damage and a trick up their sleeve (2 for slam).
  • Phase 2 (skippable) The shadows hammer is imbued with power and uses a devastating flame line attack. 2 glass clones split off from the shadow after Crushing Leap (Off by default).
  • Phase 3 The shadow splits into 2 (50% HP Each for 1-2 players) halving the firepower of its abilities.
  • Phase 4 The shadow becomes invulnerable and summons shadows of his enemies, survive until the shadow's shield falls, it'll slowly start stealing items destroy him quickly (toggleable).

How to Activate

There's an Obelisk where you first spawn on the moon. Activate the Obelisk if you want the challenge of Umbral Mithrix or don't for the vanilla Mithrix experience.

moon obelisk

Config Info

The mod is highly configurable. You can edit config values in-game and during runs through Settings -> Mod Options -> UmbralMithrix. Stats are calculated at the start of each phase so if you're blasting through Phase 1 you can make the other phases harder. If the in-game values are too limiting you can edit the modman config to input custom values.

mod options



  • Adds config for phase 2 clones after crushing leap (for extra insanity)
  • Adds config for phase 2 Lunar Devastation (didn't think ppl liked this attack)


  • Adds config to toggle umbra effect
  • Changes some config values (removes some, edits others)
    • reduces CrushingLeap by 1s
    • increased pizza waves by 1
    • reduces pizza duration to 6 secs
  • Reduces Doppel Phase 4 Mithrix HP (No Loop 0, Loop 5x)
  • "Reworks" Phase 2
    • Full Pizza (x2 the config)
    • Removed "new" pizza (shockwave)


  • Fixes Blacklist not being applied for "Vanilla" Phase 4
  • Adds large Flame Pillar and HammerSlam shockwave to Phase 2
  • Halves the Flame Pillar size for Phase 3
  • Removes Phase 3 HammerSlam clones
  • Adds config to skip Phase 2 for a more casual fight
  • Removes Lunar Chimera from Phases 2 and 3 (in a hacky way)


  • Fixed "Vanilla" phase 4 having an HP boost
  • Doubles config value for phase 4 super shard CD (change to 4 if you're updating)
  • Extends clone spawn distance so they can spawn at the edges of the arena
  • Extends HammerSlam clone duration to match sprint bash (4s)
  • Halves Phase 3 HammerSlam clones to 1
  • Halves Phase 2 CrushingLeap clones' duration


  • Replaces Skyleap with CrushingLeap
  • Adds config for CrushingLeap aim duration (configurable mid fight)


  • Changes README
  • Switches Phase 2 Ult wave to the Hammer Slam wave
  • Adds SuperShardWeight to config (how many shards are in 1 super shard)
  • Adds Phase 2 Ult Super Shard Interval to config (how often it fires)
  • Reduces default Super Shard Weight from 12 -> 6 so they're not an insta kill
  • Added Github link to page


  • Makes Phase 4 Vengeance event a config option
  • Replaced mountain shrine with obelisk next to where you spawn on the moon
  • Removed blink (messes with hammerslam)
  • Adds extra clone to HammerSlam
  • Adds Super Shards to Phase 2 Ult


  • Fixes vanilla mithrix not working after hitting the shrine on a previous run (both regular and phase 4)
  • Switches Imp Blink with Huntress MiniBlink since u can cheese him by standing at the edge of the map
  • Reduces Phase 4 HP buff (3x instead of 5x)
  • Updates Vanilla description values in config
  • Removes damage config affecting phase 4 mithrix


  • Fixes umbras getting blacklist items
  • Fixes dios making Mithrix invulnerable for 20 secs


  • Makes README more clear
  • Reduces Phase 3 HP percentage
  • Makes new item for Umbra-fication so it doesn't conflict with other vengeance mods (Cheers to Moffein)
  • Fixes Phase 4 buggin out sometimes
  • Fixes UmbralMithrix staying activated after hitting the moon shrine


  • Fixes README
  • Adds Mountain Shrine on the moon to activate Umbral Mithrix (Cheers to Race and Cap)
  • Replaces Mithrix's dash with an extended imp dash (can also dash in mid air now)
  • Removes Projectiles from Bash, Slam (Keeps orbs), Dash
  • Adds deteriorating glass clone to attacks, Slam and Bash (last 4 seconds)
  • Glass Clones release a super shard when they Bash
  • Fixes Phase 2 HP being too low
  • Adds 2 glass clones on Phase 2 skyleap
  • Blacklists some items from Phase 4 doppels (Spare Drone Parts, Empathy Cores, N'kuhana's Opinion, Razorwire, Tesla Coil)
  • Removes faster escape flame lines for less lag (in case using voidling escape or something)


  • 1 Glass Mithrix's for Phase 2 (66% HP Each Mithrix) (if > 2 players 1 more spawns and each has 100% HP)
  • Changes extra Mithrix Phase 3 HP (66% HP Each) (if > 2 players 100% Each)
  • Reduces Phase 4 invulnerability time to 20 sec base
  • Reduces Phase 4 steal time to 0.75 sec


  • Reduces some config stats to account for the clones
  • Makes Mithrix an Umbra
  • Adds deteriorating clone on skyleap for phase 1 and 3 (if > 2 players)
  • Adds 2 Glass Mithrix's for Phase 2 (33% HP Each Mithrix) (if > 2 players 2 more spawn for a total of 5)
  • Adds 1 Mithrix (2 total) for Phase 3 (66% HP Each)
  • Changes dash and bash sound
  • Reworks Phase 4
    • Mithrix's Shadow is invulnerable and immobile for 30 secs (less time based on your loops)
    • The Shadow has 5x HP (10x if looping)
    • Umbras of all players spawn at the center of the arena
    • The Shadow will start stealing 1 stack of items every 1 seconds after it's shield falls (15 sec max - decreased based on loops)

Available versions

Please note that the install buttons only work if you have compatible client software installed, such as the Thunderstore Mod Manager. Otherwise use the zip download links instead.

Upload date Version number Downloads Download link  
2022-10-5 1.4.1 132 Version 1.4.1 Install
2022-10-4 1.4.0 360 Version 1.4.0 Install
2022-9-26 1.3.0 1583 Version 1.3.0 Install
2022-9-24 1.2.3 721 Version 1.2.3 Install
2022-9-17 1.2.2 1302 Version 1.2.2 Install
2022-9-12 1.2.1 1141 Version 1.2.1 Install
2022-9-12 1.2.0 248 Version 1.2.0 Install
2022-9-8 1.1.3 687 Version 1.1.3 Install
2022-9-6 1.1.2 322 Version 1.1.2 Install
2022-9-6 1.1.1 111 Version 1.1.1 Install
2022-9-5 1.1.0 165 Version 1.1.0 Install
2022-9-3 1.0.1 316 Version 1.0.1 Install
2022-9-3 1.0.0 53 Version 1.0.0 Install