Player flees

• In the Ziggurat don't open the sarcophagus and instead leave.

Achievement: Sleeping Dogs

Player kills Agathoth

• Kill Agathoth via combat or by blowing up the Ziggurat.

Achievement: Godless World

All unlock achievement: Novus Ordo Seclorum

Antidas reigns
Awaken Agathoth in the Ziggurat and convince Antidas to be his servant.

Serenas reigns
Awaken Agathoth in the Ziggurat and convince Serenas to be his servant.

Meru reigns
Awaken Agathoth in the Ziggurat and convince Meru to be his servant.

Paullus reigns
Awaken Agathoth in the Ziggurat and convince Paullus to be his servant.

Miltiades reigns

• In Teron complete all Miltiades' side quests, which start in the Market. This ends with Miltiades standing opposite Feng's house, where he gives the player several hundred gold.
  
• In Maadoran complete all Miltiades' side quests, which start in the Slums. This ends with Miltiades in a villa in the Trade district, where he gives the player several thousand gold.
  
• In Ganezzar save Elias, agree to Lord Darganus' quests, and kill Pancratius and his followers.
  
• Convince Lord Darganus to contact Miltiades.
  
• Agree to Miltiades' plan and talk to Hector. This ends with Miltiades in Lord Darganus' house.
  
• Awaken Agathoth in the Ziggurat and convince Meru to be his servant. Miltiades should be in Meru's court.
  
• Convince Meru to bring Miltiades with him to Agathoth.

Achievement: Checks and Balances

Player reigns

• In Teron convince the preacher by the fountain you're the Chosen One.
  
• In Teron kill Cassius for Feng.
  
• Ensure Meru remains in control of Ganezzar as you're the Chosen One in his religion.
  
• Awaken Agathoth in the Ziggurat and convince him to make you his servant.
  
• Go to Ganezzar and kill Meru.
  
• Convince everyone to make you the new leader. Feng will vote against you if you betrayed him in Teron.

Achievement: The Chosen One, Novus Ordo Seclorum

Player ascends

Requires perception 8, constitution 7, and intelligence 7

• In Teron get the Grooved Sphere from Gracius. You can also get if at Harran's pass from Bass' dead body.
  
• In the Library of Saross' secret room use the Grooved Sphere to get the surgical kit (requires perception 8).
  
• Find the Monastery's Medical Chamber either using the sewer in Maadoran or the tower at Zamedi.
  
• Go to Al-Akia. If Meru is with you either sabotage the ritual or kill him after the ritual.
  
• At Hellgate find and give the The Divine Spear to Bentanagbal. Ask about the Surgical Kit and agree to him performing the ritual on you (requires constitution 7 and intelligence 7).

Achievement: Take Heed And Bear Witness, The One God

Requires Constitution 7 and Intelligence 7.

Do the following:

• Talk to Meru in Castle Ganezzar.
  
• Take the seat in the Ganezzar Star Room.
  
• Help Meru complete the ritual at Al-Akai.
  
• Ally with Balezaar.

Then perform the following steps for each ending.

Balezaar reigns

• Go to the Ziggurat.
  
• Kill Agathoth via combat or by blowing up the Ziggurat.
  
• Return to Balezaar.

Achievement: Godless World, Kingdom of God

Balezaar defeated by Agatoth

• Go to the Ziggurat and ally with Agatoth.
  
• Return to Balezaar and endure his attacks.

Achievement: Novus Ordo Seclorum

Balezaar defeated by spear

• Go to Hellgate and get the spear artifact.
  
• Go to the Ziggurat and ally with Agatoth.
  
• Return to Balezaar and use the spear on him.

Achievement: Desperate Times

Requires perception 8, intelligence 7, constitution 7, and strength 7

• Join Imperial guards and kill Antidas.
  
• In Maadoran go to the abyss (requires perception 8, intelligence 7, constitution 7, and strength 7) and power up the machine (lore 8).
  
• In Ganezzar go with Meru to Al-Akia and sabotage the ritual.
  
• Go to Ziggurat and awaken Agatoth.
  
• Talk to Paullus.

Achievement: Kingslayer, Great Vengeance and Furious Anger, Burn it