Preface

 
To start, this all began because I really wanted to get the overloading worm logbook drop. From that point things snowballed into an 8 hour long run and my poor decision to fight Mithrix at the end of it. 
 
I played on Monsoon difficulty with artifacts of Command (choose items), Dissonance (monsters appear outside of normal areas), Sacrifice (monsters drop items), Swarms (doubled spawns, halved health), and Soul (dead monsters leave wisps). The run was unmodded but I did attempt to use a macro to fight Mithrix while I left my computer on for a few hours. 
 
I describe a bit of the items I use below but if you aren’t interested in the technicalities, skip to the observations where things become more strange. 
 
 

Item Builds

 
It’s no secret that Artifact of Command is broken. With Crowbars, Will’o’the’Wisps, Ceremonial Daggers, and Guillotines it’s possible to have levels practically beat themselves after killing only one monster. This works until later into the game when spawns become so rare that the knives deactivate before new monsters arrive. 
 

Atomic Build:

 
100 Will’o’the’Wisps – Killed monsters explode. 
5. Crowbars – Monsters near full health take extra damage (ie. instantly killed by the explosion). 
5. Guillotines – Instantly kills elites after they fall below a certain point on their health bar. 
1. Ceremonial Daggers – Killed monsters release magic knives. 
 
After killing a monster, it explodes, killing nearly every other monster on the map. Each body releases magic knives which instantly kill the next monsters that spawn. The cycle continues perpetually unless spawns become too rare. Artifacts of Soul and Swarm were enabled to complement this build: more monsters with half their base health can explode more readily to deal more damage. Leaving wisps behind allows for even more damage in the chain explosions. 
 

Overheal Build:

 
100 Bustling Bungus – Regenerate health after standing still; will also heal your drones or ghosts if you have Happiest Mask equipped. 
15. Personal Shields – Boost max health with a shield. 
2 Aegis – Extra healing is converted into a temporary shield, caps at double max health. 
2 Rejuvenation Rack – Double the strength of healing. 
Infusions are optional 
 
Stand still for a few seconds for the bungus to activate and gain a massive shield, largely helpful for tanking damage, but it becomes less important later on when ANYTHING can break your OST (one shot protection). At that point just stack hundreds of teddy bears. 
 

Bonarable Bentions

 
Crit Glasses 
Goat Hoof 
Attack Syringe 
Charged Perforater 
Brilliant Behemoth 
 

Metagaming –not rlly

 
To summarize, start looking at the item pool more like this: 
 
 
 
Of course this isn’t the end all be all, just an idea of what items are important after maybe stage 30. 
 
 

Observations

 
This is probably the third or fourth time I’ve clickbaited you by saying RoR2 is really weird in late game, but it is true. The following are some strange discoveries I noticed. 
 

Difficulty

 
Difficulty appears to cap at mob level 99. It does not move past a certain point on the slider. 
 
 
 
 
While it seems not to move, the difficulty does continue to increase at least as stages continue. This is evidenced by the ever-inflating cost of drones and that Aurelionite’s health would continue to increase on successive visits. Whatever the reason, bizarre indeed. 
 

Combat Shrines

 
These things straight stop working after a while. I’m not sure if it correlates to the difficultly level or how many you have activated previously in the run, but eventually you no longer have the option to use them. They spawn but the purple floating icon doesn’t appear nor will it allow you to spawn any monsters. 
 

Monsters and Spawns

 
The number of monsters typically increases throughout a run of RoR2, but after a point the spawn rates begin to significantly drop off. As difficulty increases, you will find more and more bosses but less and less normal monsters. Eventually these bosses are replaced by elite bosses which are eventually replaced by scavengers and elite scavengers. 
 
The game seems to view scavengers as the most difficult unit and can only spawn variants of them after the difficulty reaches a point where not even elite bosses are difficult enough for the player. Some time into the run you will only be able to find Celestine and Malachite Scavengers, in varying numbers. The spawns of these buff bois continue to dwindle further into the game but the quantity of scavengers in each spawn appear to increase. 
 
The strange behavior peaks from stage 60 onward as some rounds are completely devoid of spawns at all. Teleporters will occasionally lack a boss, so the only scavengers you encounter are randomly spawned. On fewer stages there is no boss OR random spawns. You are free to activate the teleporter and simply proceed to the next stage. 
 

Inflation and the Abstraction of Money

 
At first, item prices seem normal. Then they become expensive, but not particularly ludicrous. 
 
Stage 51 Gun Turret 
 
 
Stage 58 Gold Totem 
 
 
Stage 59 Legendary Chest 
 
 
All the while though, your wallet starts to act strangely. This may have to do with Ghor’s Tome, but it is possible to achieve a negative balance. You are indebted to the planet. 
 
Stage 43 
 
 
Stage 44 
 
 
Not only that, but after long enough, even pickups are in the negatives. 
 
Stage 64 
 
 
Stage 79 
 
 
Stage 96 
 
 
-2,147,483,648 seems to be the HIGHEST value reachable in RoR2. It is also worth noting that the scavengers you are killing at these levels drop so much money you can basically purchase anything you want, regardless of negative balance or cost. 
 
It was pointed out in the comments the reason for this, image below 
 
 

Bosses

 
Bosses start getting really scary in the late game with some ridiculously large health bars. In order of increasing terrifyingness: Alloy Worship Unit, Aurelionite, and finally Mithrix. The former two can only reasonably be defeated by blowing up dozens of scavengers to deal damage in the millions. Note: Alloy Worship Unit can be defeated by smashing it into walls really hard. In my own run I was pretty dumb and focused only on chain damage through the Atomic Build, and did not focus on primary damage. If I were smarter, I would have stacked a few hundred armor piercing rounds. This became a huge problem on stage 101 during my fight with Mithrix. 
 
Stage 54 Aurelionite 
 
Stage 59 Aurelionite -2,147,483,648 
 
 
 

The Actual Mithrix Fight

 
To be honest I went to the moon thinking the fight would be easy. Some lemurians and stone golems appeared weirdly. Charging the pillars was a breeze. I arrived at the arena expecting a quick fight and to melt Mithrix. 
I 
Was 
Wrong 
♥♥♥♥♥♥♥♥♥ he has more health than everything I had previously killed combined. I shot at him fire for ten minutes and did maybe 1% damage. At that point I almost gave up but decided to set up a macro to rapidly click M1 and M2 for a few hours so I could go to sleep. 
 
It lasted for about two and a half hours before Mithrix burned through my 5 Dio’s Best Friends. He was at maybe 2/3 total health, still on phase 1 at the end. 
 
Here’s a timelapse over two and a half hours until I died. 2nd vid is far longer and covers the stages leading up to the fight. 
 

 
The fight is impossible unless you come specifically prepared. 
 
 

Lore?

 
While none of this is official obviously I like to think that the strange behavior of the game has a reason. As your survivor obtains the power of god, they repeatedly visit the same stages wiping out increasingly powerful populations of the local monsters. The longer you go on, the harder the fight the monsters put up against you until you have wiped out the strongest among them. Eventually there aren’t even any average monsters left and the planet is only roamed by the strongest of elite bosses. You kill these too and after that the planet is only roamed by the strongest tribes of scavengers, who pop up like weeds even when you exterminate them. 
 
When you eventually find yourself in front of Mithrix you may be nearly invincible, but so is he. He stalemates you for a near eternity as a cost for your crime. The fight lasts until one of the two of you die. 
 
In essence: If you thought RoR2 was about British colonialism it’s actually about genociding the local fauna of a planet and going toe to toe with god. 
 
 

Reflections

 
It was certainly fun going so deep into the game, but I never did get the overloading worm logbook. Kinda sad. But it did inspire me to write this ♥♥♥♥♥♥ steam guide. 
 
Maybe someone has done this before, but if anyone does ( has) actually manage (managed) to defeat Mithrix after Stage 100 that would be awesome, let me know in the comments. Make sure you deal enough damage with your primary weapon, don’t rely on scummy Will’o’the’Wisp chains like I did. Probably collect 500 Tougher Times and 10 Dio’s Best Friend. That sounds hard to do but you get ***loads of item drops late into the game with Artifact of Sacrifice, it’s more work to collect them than earn them. 
 
Death 
 
 
 

Extras:

Memes

Recordings

Screenshot Gallery

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Aye drop a like if you feel so generous 
 

Hope you enjoy the post for Risk of Rain 2 Challenging Mithrix on Stage 101 – the LATE Late Game, If you think we should update the post or something is wrong please let us know via comment and we will fix it how fast as possible! Thank you and have a great day!