In a time before recorded history, so far in the past that the whispers of stories told from one individual to another had long since withered and faded away, the portals were made. Areas of magic so strong that the four elements combined into a powerful door which could transport a traveler completely from one end of the 'verse into another, connected only by invisible waves of intertwined magic.
When Willow discovered the portals, they had existed dormant for eons – waiting for the moment when someone with a connection to elemental forces would come to them carrying an item of significance – a talisman which would awaken the tendrils of power which could pull them through space to the other side.
The portals appear as old television sets, flickering on as the adventurer draws near with their talisman. In worlds where technology is less developed, the old magics appear to have some kind of transformative cloaking device so as not to draw overwhelming attention from the original denizens of those worlds.
Stable portals are areas where the elemental magic is constantly strong on both sides of the connection. These places require little maintenance as they hold the doorways open naturally.
Unstable portals have wavering levels of elemental forces on one or both sides of the gate. They may hold for a period of time without intervention, but after that time has passed, the power dissipates and wavers, and requires outside influence to re-establish the connection.
Lore written by Minimaid