Mortis monolith

During the Clone Wars, in a Wild Space star system named Chrelythiumn, a massive octahedral monolith appeared, containing a vergence in the Force that functioned as a portal to the realm of Mortis. On the outside, the octahedron was 5 kilometers long, both deep and wide, and was etched with red lines and a black surface.

When the monolith revealed itself by sending out a 2,000-year-old distress signal, only the Chosen One, Anakin Skywalker, and his Jedi companions were able to see the monolith from their shuttle, as the Galactic Republic forces Skywalker was supposed to rendezvous with were oblivious to its sudden appearance. This was because the Father, a powerful Force wielder living on Mortis as an anchorite, sought an audience with Skywalker to test if he truly was the Chosen One and had lured him there.

Once Skywalker and the shuttle, along with the Padawan Ahsoka Tano and Jedi Master Obi-Wan Kenobi, noticed the appearance of the monolith, its gravitational force pulled the trio into its gateway, bathing them in a blinding white light. When the trio came to some time after, they awoke on the terrestrial realm of Mortis. The monolith disappeared after Skywalker and his companions eventually escaped Mortis, with no evidence of its appearance left behind in the star system.