Orokin Moon/Speed Test

In this room, there will be 2 Thumper Death Orbs in the center. Shoot the plate in the upper part of the center and 2 doors will open (see minimap for the hidden rooms). Go into one of the doors. 1 side contains ice hazards while the other contains many Thumpers. Make your way to the end and shoot a plate above the final door. Then complete the other room, shooting the second plate. The cylinder in the starting room will rise up and unlock the gate to the portal above.
 * If no plate is at the end of the room, it means that the test has failed.

This test rewards Speed Drift.