Right now I'm supposed to get the 3 items for Jack's Squad. I have the Hydro Apple and Ice-10, just need one more. I'm sure it's on that teleport hell area, but it feels like I'm walking in circles now... Some directions would be nice.
It's a little confusing, even with the maps, but this honestly made Eridanus significantly simpler for me.
Metal X is not, as I recall, within the teleport hell itself. The maps from that site use numbers in blue/red to correspond to teleporter entrances and exits. Follow the guide to navigate the way out of there. You'll come to an area now with staircases and pitfalls (because teleporters weren't enough). You'll have to go through a couple invisible doors but they're marked on the map. When you find the right staircase, switch to the 2f map to find the correct pitfall (which are colored black). The numbers on the 1f map that have the kanji next to them and are just in a white square indicate where you'll land on the first floor through one of the pitfalls. yar!