ULTRAKILL Minos Prime: How To Access The First Prime Sanctum

ULTRAKILL Minos Prime: How To Access The First Prime Sanctum
Images via New Blood Interactive

Written by 

Tarran Stockton


19th Aug 2022 11:53

The ULTRAKILL Minos Prime boss is one of the most difficult encounters in the game, but the journey to face them as just as hard due to the criteria you need to meet. Each act of ULTRAKILL has a super secret mission called a Prime Sanctum, but gaining access to these requires you to get a perfect score on every previous level, which can be quite an undertaking. So if you're looking for a breakdown of how to access the Act I Prime Sanctum and take on the ULTRAKILL Minos Prime boss, we've got you covered. 

  • Make sure to also take a look at our ULTRAKILL tips for some advice on the different tricks you can perform, and how the movement mechanics work. 

ULTRAKILL Minos Prime: How To Access The First Prime Sanctum

ULTRAKILL Minos Prime: How To Access The First Prime Sanctum
Click to enlarge

Before you can just jump into the first Prime Sanctum level and fight Minos Prime, you will need to get a P rank all the levels in the prologue and Act I. To do this, you will have to get an S rank in all the categories that appear in the mission summary screen, which are time, kills, and style. In addition, you cannot die or restart from a checkpoint during a mission or you will lose your chance at getting the P rank. 

The next step is to load back into the first mission for the Gluttony layer, called Belly of the Beast. Progress through this level, and once you get past the fight with the three Cerberus enemies, you will come into a room with tonnes of walkways leading upwards.

Clear the room of enemies first, and then look down for a walkway that's disconnected from the rest. Drop down onto it, and follow it forward through a flesh door, where you will find the door leading to the Prime Sanctum. Enter inside and drop down the shaft to start the level. 

ULTRAKILL Minos Prime: Defeating Minos Prime

ULTRAKILL Minos Prime: Defeating Minos Prime
Click to enlarge

After loading into the level, grab the torch in front of you and follow the spine walkway all the way until drop into a flesh door, where you can place the torch on a pedestal. Head through the door that opens, get the checkpoint ahead, and then prepare to face the Flesh Prison enemy. 

The Flesh Prison is the first part of the Minos Prime boss, and it's basically a rotating cube suspended in the middle of the room. Because of its size and stationary nature, the Flesh Prison is extremely easy to hit, however it can throw out a tonne of attacks and even heal damage. 


The main attack you need to worry about is when it spawns a series of eyes that shoot lasers at you. While their attacks are easy to dodge, the Flesh Prison can grab and eat them to regain health, so you should always prioritise killing all of them when they appear. The other major attack to worry about is the beam of light. This is telegraphed by a white circle on the floor, so get out of the range instantly, as it deals massive damage on a direct hit. 

After defeating the Flesh Prison, Minos Prime will be freed for you to fight. A short cutscene will play out as he thanks you for freeing him before deciding you still need to be killed, and the second boss fight begins. For this fight, you will generally want to stay close to him to consistently heal, and keep to the ground to avoid his more damaging attacks. 

He will throw out a lot of combo attacks of punches and kicks, and these will also get faster once he reaches half HP, but they can be dodged by dashing away once he telegraphs them. He also performs different teleport attacks to either close the distance, or slam down to send out a shockwave, which can be dodged with a well-timed jump. Making good use of the railgun will allow you to deal lots of damage here, while parried shotgun blasts should be your go to between recharges. 

Once you defeat Minos Prime, a door will open where you can leave the level and read a terminal for some extra lore. 

That's all for our breakdown of the ULTRAKILL Minos Prime boss fight, and now you know how to access the Prime Sanctum secret level in Act I and defeat the boss. 

Tarran is a Senior Guides Writer at GGRecon. He previously wrote reviews for his college newspaper before studying Media and Communication at university. His favourite genres include role-playing games, strategy games, and boomer shooters - along with anything indie. You can also find him in the pit at local hardcore shows.

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