stone skull.

From the room with floating skeleton heads, proceed to the next room containing Gorgons.

Above the Gorgons, a path leads to a new area. To the left of this area is a save room.

Exit the save room, go right, then head up and exit through the door on the right.

In the next room, you'll encounter more skeletons and Gorgons. Climb upwards, noting small areas where you can drop down to find items.

Collect an antivenom and a potion from two of the three drop-down sections.

At the top of the room, take the door on the left.

This vertical room features Medusa Heads spawning continuously from both sides. Use the gravity jump to reach the top right.

The room after the Medusa Head room has a formal background with red accents. At the beginning, find a Library card between two traps.

Navigate through sections with floating heads and traps, timing your jumps carefully. Removing nova skeletons can help.

After the first section, jump to the platforms on the top left to continue.

The following section contains candles with money.

The last section is similar to the first but without floating heads or stone skulls. Exiting this section concludes the Marble Gallery and leads to the beginning of the next castle section.

To proceed to the Outer Wall in the INVERTED castle, backtrack to the area where you dropped from when exiting the Underground caverns. Look for the red platform in the ceiling.

Take the left path towards the Outer Wall.

In the next room, a path to the bottom left leads to a green door. Go through it to find the Meal ticket item.

Return and take the top left pathway. A second red platform leads to a hidden room above.

In the hidden room, you will find the Iron ball item. Exit the room and proceed left.

You will enter a horizontal room with stone skulls moving up and down, along with some skeletons and corpseweed.

Exiting this horizontal room brings you to the Outer Wall.