Here is the full list of all 24 Oracle achievements. It takes around 1-2 hours to unlock all of the achievements on Windows.
Find the hidden passage.
Visit the ruins.
Explore the corn field.
Explore the wrecked coal mine.
Find the old outpost by the river.
Find the Gorge.
Explore the maze.
Find the grave of the Fallen.
Red tree inside the Pit?
Explore the boats by the shore.
Remember her neck tattoo.
Explore the wooden windmills.
Explore the Radio Station.
Explore the mine that goes on top of the mountain.
Visit the Tower.
Magic under the Roar.
Visit the railroad and the train wreck.
Cross the wooden bridge.
Walk under the waterfall.
Swords and Skulls.
Explore the Graveyard.
Explore the Church.
Explore the tombstones.
Wake up on the Island.