Proving Ground is a Quest in Divinity: Original Sin II. Entering the portal, you face yet another challenge similar to the other trials of the One back at Driftwood and Fort Joy. Will you triumph and be worthy of the title of "The One"?
- Enter the portal.
- Speak to the Spirit Bird.
- Kill the Great Guardian.
- Report back to the Spirit Bird.
In the Teacher's Hall at the Academy, there is a door that can be lockpicked. Entering the room beyond, which is called "Armaments of the One", you will immediately be awarded 27,900 Exploration XP. Head towards the portal and enter it.
Upon entering the portal, you will gain another 41,850 Exploration XP. Continue onwards and you will see the body of a dead bird. Cast Spirit Vision to see the spirit of the bird, and speak to her. Agree to her challenge to fight some battle-hardened construct.
Enter the vast chamber, and you'll find a huge guardian there called "The Great Guardian", along with 2 Eternal Protectors and Eternal Sentinels. He will demand you leave, and if you try to move closer, he will initiate combat. It is not a difficult fight, and if you kill the Great Guardian, all the smaller constructs will be destroyed. The Eternal Protectors and Eternal Sentinels are worth 27,900XP each, while the Great Guardian himself is worth a whopping 97,650XP. All the smaller constructs will award XP upon death regardless if they were killed by your hand or because the Great Guardian died, so needless to say the most optimal way is to simply focus fire and destroy the Great Guardian. When killed, the Great Guardian drops the "Blade of the Swornbreaker", one of the pieces to craft the Swornbreaker weapon, as well as several Divine-quality loot.
If you are having difficulty with this fight, there are Eternal Reflectors here that can be moved, with a phase conductor that is located behind the Great Guardian. Placing a Phase Capacitor on the conductor can shoot a beam forwards onto the reflectors. Directing the beam at the boss will stun it and keep its magic armor at 0 for as long as the beam is focused on it. You can use invisibility potions or spells to do all this without being noticed. Ultimately though, the simplest solution is to cast a powerful source spell such as Meteor Shower or Hail Storm, and since the Great Guardian is so big, nearly all the shards will hit it, resulting in a quick one-shot kill move.
In any case, once the Guardian is a pile of trash heap on the ground, report back to the Spirit of the Bird, and you will be deemed worthy of being "The One". The quest is not removed from the journal, though.
- 27,900 Exploration XP upon entering the "Armaments of the One" room.
- 41,850 Exploration XP upon entering the portal.
- 27,900XP for each Eternal Protector and Eternal Sentinel, plus 97,650XP for the Great Guardian, which adds up to a grand total of 209,250XP.
- "Blade of the Swornbreaker" crafting material on the body of the Great Guardian.