Here is the full list of all 25 The end is nahual: If I may say so achievements worth 1,000 gamerscore.
Obey your master
Disobey your master, this is not an achievement and you shall not feel proud about it
Constants and Variables
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Jacob didn't get hit enough in the third trial
Defeat your creators without Jacob dying
Defeat the low level warrior without dying
Just press the counter button on the right time
Jacob didn't die or lost in the second trial
Jacob didn't die or lost in the first trial
Get the neutral ending
Defeat your creators
Defeat the Jaguar warrior without Jacob dying
Defeat the Jaguar warrior
Defeat the eagle warrior without dying
Defeat the eagle warrior
Defeat the first warrior
Finish the Third spiritual test
Dying and ballin'
Finish the first spiritual test
Listen to all of the mural stories without skipping them, good for you
Finish the cihuanahuallis' tests
Destroy the outer body of the piano and don't eat the soul
Sammael defeated Jacob's army
Finish the tutorial, let's move on