Obelisks are player-built structures usually casting Soul Effects on nearby remnant players. Their function depends on the Runestones used and they absorb the power of the souls trapped in Soul Sand and Soul Soil.
The Obelisk’s core is made of different Runestones, having a maximal width of 5 blocks and a maximal height of 20 blocks. Each layer of the core must have the same kind of Runestone.
The core is encased in a frame of full Tachylite blocks as seen in the picture below.
An Obelisk also requires Soul Sand or Soul Soil in order to power up with increasing needs as the width of the Obelisk is expanded.
Soul Sand and Soul Soil must be placed below the Obelisk with a clear line of sight in between block and structure.
The valid area to place your Soul blocks is a square with the side length
10*width of the core with the Obelisk in its center.
An Obelisk will affect remnant players in a square shaped area of
10*width+10 blocks radius.
Tachylite Runestones are the defining factor of an Obelisk. The basic Tachylite Runestone can be crafted using 8 Tachylite and 1 Crying Obsidian.
It can then be imbued using Ichors and will adopt the respective Soul Effect. Once they are imbued they will grant their Soul Effect to remnant players when included in an Obelisk.
The Ichors can be changed by using dispensers, for example activating a dispenser containing an empty Soul Vessel and facing a Tachylite Runestone with Attrition will render the Obelisk neutral and fill the Soul Vessel with Ichor.
The Soul Rift can be crafted using 4 Tachylite Runestones, 4 Crying Obisian and 1 Enderpearl. Once implemented into an Obelisk, it will allow dissociated remnant players to teleport between different Soul Rifts as long as they do not have Attrition IV. Rifts will also increase the level of Attrition upon teleportation.
Active Soul Rifts also have the side effect of attracting Ethereal Morticians to roam around their Obelisk.
Once you click the Soul Rift as a dissociated player you will see 3 different symbols:
This icon is assigned to the Obelisk with the Soul Rift you clicked
Available teleportation destinations will be marked with this icon
The currently selected destination Obelisk will display this icon along with the coordinates of the corresponding Soul Rift
Tachylite is the base material for Obelisks. It can be made from 4 Obsidian, 4 Basalt and 1 Filled Soul Vessel and its durability is halfway between Obsidian and Basalt.
In addition to Tachylite stairs and slabs, there are multiple other versions of this block type.
Chiseled Tachylite can be crafted by putting 2 Tachylite blocks on top of each other in a crafting grid. Just like normal Tachylite, chiseled Tachylite can be used to build Obelisks and has stair and slab variants of the block.
There is also a Chiseled Tachylite Pillar made by putting 2 Chiseled Tachylite blocks on top of each other.
Scraped Tachylite can be found as parts of derelict Obelisks and can be mined to be used as Obelisk frame and building block.
Derelict Tachylite can only be found as a part of a Derelict Obelisk. Breaking it will grant large amounts of experience and has a 20% chance on dropping a Shattered Soul Vessel. The Fortune enchantment increases this chance by 10% per level.
Derelict Tachylite is the only Tachylite variant that can not be used as an Obelisk frame block.
Derelict Obelisks are abandoned structures spawning in Soul Sand Valleys. They include Derelict Tachylite and are therefore a source of Soul Vessels. They also have a 1 in 3 chance to have a Mortician roaming the area.