This mystery can be found on the coast in the south of Suthsexe, about 920m southwest of Crawleah, AC Valhalla.
How to Complete the Suthsexe Anomaly - Seven Sisters - AC Valhalla
The structure of this anomaly is relatively simple, but there are some tricky parts where you’ll need to navigate moving red blocks. If you hit the blocks, you’ll be transported back to the previous checkpoint.
The firs thing you’ll need to do is slide down the first slope while gliding either side of the red blocks. At the end of the slope, be sure to jump to the next platform. Turn right on this platform, then follow the smaller platforms until you reach the first unstable structure. You’ll need to climb up this and then point the projector on an unstable structure below you, to the left of where the projector was initially pointing. You can now slide down the slope to the platform where the projector is pointing, but you’ll need to avoid the red block as you slide down.
The next sloped platform with moving red blocks can be tricky to navigate. Jump into the centre of the sloped platform, and be ready to move from side to side while avoiding the moving red blocks. You might need a few attempts at this one, but try not to panic if you’re too close, leaving you vulnerable to adjusting too much to one side. Once you’re beyond the red blocks, be ready to jump at the bottom of the platform to the next flat one.
Follow the smaller platforms until you reach the next series of platforms with moving red blocks associated with them. This time, you’ll need to begin jumping over the thin platform when the horizontally moving red blocks are closest together. The same goes for the vertically moving red blocks after it. Once you’re through, you’ll encounter another small slope, and then a larger slope with more red blocks on it.
The red blocks on this next slope protrude in and out of the surface of the slope. You should begin just as the first red block at the highest point on the slope recedes, then trust that you have enough time to slide down at the bottom. If you try to jump too soon here, you’ll be transported back. You should only jump once you’ve slid beyond each of the red blocks, and only then at the point shown in the screenshot below.
Once you’ve sucessfully jumped from the last sloped platform, follow the linear path to the projector. You’ll need to move this away from the unstable platform and wait for it to move upwards. Point the projector at the unstable platform again to make it stop at its highest point, just below the highest static platform. You can then jump to it, and then onto the lower unstable platform toward the next projector. Once here, point the projector away from the nearest unstable platform, and wait for the further one, which you first jumped on, to move down until it’s level with the platform to your left. You can then jump on the unstable platform and follow the linear path to the end of the anomaly.