Sejan cave

The Sejan cave (not to be confused with the Sejan beach cave) is located in the middle of the eastern side of Sejan peninsula's central mountain range. It's a dark, maze-like system of tunnels that's easy to get lost in. Sinister secrets lurk within the depths of the cave, waiting for a hapless adventurer to stumble upon them.

Venturing in alone
The cave can be discovered by the player themselves. Without a mean of illumination, like a torch, the player can't go very far into the cave. Even with a torch, they are soon confronted by a deep drop that seems to be the only way further into the caves. The player needs a rope to descend to the lower chamber. This rope stays in the cave permanently and can be used on any further visit, including the adventure that is elaborated upon below. When reaching the lower chamber, the player can attempt to explore the surrounding tunnels but can't find anything. This is to be expanded upon in later updates.

Shyni's adventure
Perhaps the most common way to be introduced to the cave is with Shyni's adventure that takes place in it. After doing some preparations for the adventure, the two set off for the cave, armed with a stone tablet that has the map of the caves carved on it. Following the directions on it, they find a chamber with an innocent-looking bowl on a stone pedestal. Touching it possesses the victim with incredible urge to commit violence upon anything or anyone in vicinity. The bowl ends up being touched by someone, and the encounter can go in multiple directions, ranging from both the player and Shyni uninjured and only slightly frightened to one of the participants ending up murdered.