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