Here is the full list of all 80 Astrea: Six-Sided Oracles achievements.
Reach max level with Hevelius.
Defeat Astrea with Sothis.
Defeat Corrupted Cellarius.
Defeat Astrea with Cellarius.
Defeat Corrupted Austra.
Reach max level with Cellarius.
Defeat Corrupted Sothis.
Defeat Astrea with Austra.
Defeat Corrupted Moonie.
Reach max level with Moonie.
Score at least 3500 points in a run.
Defeat Astrea with Moonie.
Defeat Astrea.
Defeat Astrea Avatar.
Defeat Corrupted Orion.
Spend at least 1500 Star Shards in a single run.
Open Astrea's Heart.
Reach Astrea's Heart with Orion.
Defeat Decayed Star.
Reach Astrea's Heart with Sothis.
Reach Astrea's Heart with Cellarius.
Prevent a Heart loss using Wave.
Reach Astrea's Heart with Moonie.
Own a Sentinel on max level.
Reach Astrea's Heart with Austra.
Defeat Corrupted Assembler.
Score at least 2000 points in a run.
Win a run without losing Hearts during battles. Sacrificing a Heart at Shrines doesn't count as Heart lost.
Reach Astrea's Heart with Hevelius.
Defeat Uncaged Anomaly.
Defeat Doomed Astronomer.
Play at least 10 dice in a single turn.
Defeat Sanctuary Parasite.
Forge a die.
Defeat Smoldering Beast.
Acquire a Sentinel.
Win your first battle.
Save Meissa, the Antiquarian.
Defeat a boss on the first turn.
Score at least 7000 points in a run.
Reroll the same die at least 5 times in a single turn.
Make a creature receive at least 100 Purify in a single Purify instance.
Win a run with 10 or fewer dice on your dice pool.
Win a run with at least 50 dice on your dice pool.
Win a run with only one type of dice other than Starter dice on your dice pool or with only Starter dice in your dice pool.
Win a run with two Sentinels on max level.
Win a run with at least 15 Blessings.
Win a run without owning any Sentinels.
Win a run without any Epic die on your dice pool.
Win a run without any Blessings.
Win a run at Anomaly Level 3.
Win a run at Anomaly Level 8.
Defeat the Corrupted version of yourself.
Defeat Corrupted Hevelius.
Defeat Astrea with all Oracles.
Defeat Astrea at Astrea Level 3.
Reach max level with all Oracles.
Obtain all other achievements.
Enhance an enemy die.
Make an enemy defeat themselves.
Win a battle with at least 20 Plague Hex die in your dice pool.
Deal infinity Purify.
Play at least 20 virtues in a single turn.
Defeat Astrea with Hevelius.
Repair or Reactivate Sentinels at least 20 times in a single battle.
Have both your Sentinels with 4 types of Link.
Acquire 12 different type of Sentinels in a single run.
Reach max level with Austra.
Deal 50 Purify with a Safe die.
Dodge 4 Corruption in a row.
Play a die with at least 50 Confuse on an Enemy without any Confuse percentage modifier.
Reach max level with Sothis.
Have at least 20 Soul Heat.
Have at least 30 Chanting.
Have at least 4 creatures with at least 15 affliction.
Defeat Astrea with Orion.
Reach max level with Orion.
Win a Ground Zero battle without moving your Orbs.
Move your Orbs 50 times in a single battle.
Activate Astrium 4 times in a single turn.