
Just as in the first Hades, Hades 2 features a gameplay system that allows you to apply various modifiers to make your runs more difficult and every attempt more challenging. This time, the system is known as the Oath of the Unseen. In this section of our guide, we explain how it works and how to unlock it so you can use it if you wish.
To unlock the Oath of the Unseen in Hades 2, you must defeat Chronos at least once. He is the Titan of Time and the final boss of the Underworld.
After defeating Chronos for the first time, return to the Crossroads and head towards the area containing the Silver Pool and the Training Grounds. The Oath of the Unseen will appear beside the entrances to the Underworld and the Surface. You can interact with this pillar to configure your preferred Testaments and Vows.
Inside the Oath of the Unseen menu, you will find a series of Testaments of Night that you can complete. These Testaments are generated at random and essentially require you to defeat a particular boss using a specific weapon.
However, to complete each Testament, you will need to activate Vows. Here is what you need to know about them:
Feel free to experiment with the Vows and activate or deactivate them as you please. You do not have to activate all of them or increase their ranks. Activating just one will allow you to sign a Testament and attempt to complete it, although some Testaments may require a higher Fear rating before you can sign them.
There are no negative consequences if you decide not to use any Vows. You will simply play with Hades 2’s standard settings and no active modifiers. Just remember that if you do not activate any Vows, you will not receive a reward, even if you defeat the required boss using the weapon specified by a Testament.
Activating Vows and completing Testaments from the Oath of the Unseen allows you to earn the Reagent known as Nightmare. If you manage to defeat the required boss using the weapon specified by the Testament, you will receive this special resource, which is used for upgrades at the Silver Pool.
Other than that, the Oath of the Unseen has no additional purpose beyond allowing you to customize the difficulty of your post-game runs however you like, making each new attempt more interesting.