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 Gorge.
Red tree inside the Pit?
Find the hidden passage.
Magic under the Roar.
Visit the railroad and the train wreck.
Cross the wooden bridge.
Explore the Church.
Explore the Graveyard.
Walk under the waterfall.
Visit the ruins.
Explore the wrecked coal mine.
Explore the corn field.
Explore the wooden windmills.
Explore the Radio Station.
Remember her neck tattoo.
Visit the Tower.
Explore the boats by the shore.
Explore the mine that goes on top of the mountain.
Find the grave of the Fallen.
Explore the maze.
Find the old outpost by the river.
Swords and Skulls.
Explore the tombstones.
Wake up on the Island.