At the center of Ulthuan lies the Island of the Dead, which is home to a magical vortex that siphons magic out of the material plane back into the Warp so Daemons cannot manifest. The overabundance of magic is due to the Warp Gates at the poles of the world erected by the Old Ones to travel back and forth between wherever they originated and the Warhammer world collapsed, leaking fuel and Chaos into the world.
Waystones come in all shapes and sizes, from the size of large mountains to something that can be used as a paper weight. They're found all over the world, and require maintenance and adjustment to keep them functional. In addition, they're prone to vandalism. Orcs believe High Elves to be their rivals in terms of strength, and desecrate these and rededicate them as shit sculptures (literally) of Gork and Mork (or Mork and Gork?). Dark Elves think Slaanesh is an ally, and weaken the Waystones to bring Daemonettes in for business AND pleasure. The other evil races, like Vampire Counts, use them as amplifiers for their dark magic, while humans tend to do shit like pry the giant 10 foot tall precious gems out of them or build things around/on top of them. Either way, if High Elves are going to war away from Ulthuan then it's most likely to defend a Waystone.
High Elves who die and who's souls aren't claimed by their patron gods have to make a run for the closest one where they can dwell and gain semi-corporeal forms to fight living enemies of Ulthuan in defense of the stones as well as commune with the living elves nearby or attuned to Waystones and their fellow dead but not claimed kin. Those who fail to reach a Waystone are either claimed by Ereth Khial for torture or Slaanesh for consumption.
Soulstones exist in both Warhammer 40k and Warhammer Fantasy. In 40k, they replace Waystones by containing an Eldar's soul to protect them from Slaanesh as Eldar have no Waystones or equivalents. In Fantasy, they have reduced importance, allowing a High Elf to survive something magical that would otherwise kill them, as well as attuning their soul to nearby Waystones, which gives them a built-in instinctive GPS.
On the tabletop, Waystones are special terrain that usually grant a bonus to spellcasting for the army controlling it. Games Workshop loves to use their Waystone pieces in the background of High Elf models, yet they for some reason have never released a scenery set to purchase.
Waystone as seen in Warhammer Online.
|The High Elves and their gods of Warhammer Fantasy|
|Characters:||Eltharion - Everqueen - Teclis - Tyrion|
|Cadai:||Asuryan - Hoeth - Isha - Kurnous - Lileath - Loec - Mathlann - Vaul|
|Cytharai:|| Addaioth - Anath Raema - Atharti - Drakira|
Eldrazor - Ellinill - Ereth Khial - Estreuth - Hekarti
Hukon - Khaine - Ladrielle - Morai-Heg - Nethu
|Events:||The War of the Beard - The invasion of Naggaroth|
|Misc:||Ulthuan - The Vortex - Waystone - Widowmaker|
|Appearances:||Blood Bowl - Dreadfleet - Mordheim - Warhammer Fantasy Battle|