A Keldra Gateway or Keldra Portal was an advanced magical action used as a method of teleportation. A Keldra Gateway eventually came to be known as a dreadgate by non-magic users because of their disturbing appearance, by they are named after the Eari sorceress Keldra, who was the first to discover and implement the technique. Though discovered by the Eari, it fell out of favor due to the amount of magic required to utilize it, which went against the Eari's conservative style. Other schools, such as the Draol, were better suited for the task, but the complexity of the act made it a very rare, antiquated technique.
Its last known usage was by the Draol Atury during the Great Purge; the action was beyond Atury's power and he, along with his minions and a portion of the armies who hunted him, were erroneously transported to the world of Errod. Unknown to all but a handful, Atury's mentor Orilac also utilized a dreadgate in an attempt to escape the Purge; he and his followers were never seen or heard from again.
Appearance
The portal itself appeared as a ring of dark mist surrounding by raging storm clouds, often accompanied by fire, lightning, and sometimes even thunder or a mini cyclone. It was not possible to see what was on the other side because of the mist. Any who wished to pass into a dreadgate simply walked through the mist, and had to trust that they would safely emerge from the other side.
Utilization
Using a dreadgate was considered a very advanced technique, primarily because it required a lot of magical energy to create one, especially for long distances. The portal functioned like a reverse summoning; one essentially "summons" themselves someplace else by creating a portal that essentially links vorsys between two locations. Sometimes, two spellcasters would be used, one at each location, to "share" the burden. Because of the immense amount of power required to create a dreadgate, they were rarely used. This is why a trio of vormongers collaborated to "leapfrog" their efforts during the Draol attack on Gruen that led to the Meralian Accord. While one was busy with the gateway, the others would be gathering vorsys to either take over or perform other actions.
Where Atury went wrong was in thinking it functioned similar to perciperation, where a mage can transport through time or space in the Dream Lay in order to access deep memories by focusing on the target and honing in on it. Another setback was that Atury was deaf, and any spells requiring the use of vocal speech were typically problematic for him.
Dreadgate TCG
The Dreadgate is the centerpiece to the card game, Dreadgate (TCG), where players must battle to push as many of their units through the Dreadgate as possible (there are other win conditions as well). In the game, the portal is typically the center square of a 25x25 grid, but it is possible to move the gateway.