Base (Lower Layer)
Top (Upper Layer)
There are three layers to Reshanta: Base (or Lower Layer), Core and Top (or Upper Layer). Primum Landing, for Asmodians, or Teminon Landing, for Elyos, is where you enter the Abyss. This places you in the Lower Layer.
At the Eastern Shard of Latesran and Western Shard of Latesran there are Abyss Teleporter NPCs that can send you between the Base layer and the Top layer. The shards are like pillars of energy between the two layers that can be used for transport. I do not understand the why, but there are both Elyos and Asmodian teleporters here, on either side of the pillar of energy. It would seem that they should be fighting, constantly, to deny the use of the Shard to the other side, but the guards there seem to hold an uneasy truce with the other side.
Mobs in the instances inside the fortresses may drop Icons, Goblets, Crowns and Seals. These can be sold to special NPCs at your Fortress for Abyss Points. There is also a pair of Shugos in the Eye of Reshanta, Momorinrinerk and Amarunerk, by the Divine Fortress that will pay more than double for these treasures.