Returnal is a challenging game, and one of the ways it reinforces this is with an interesting design decision involving progression. Certain Xenotech Devices players find will be carried over into subsequent cycles, and these open up a lot of mobility options for Selene moving forward. While this is great, it's odd that there are often areas that players can't access yet without this Xenotech just sitting around in the early levels. Players will know this pain from seeing orange lights with items on a high ledge that they can't reach without the grappling hook, or when they find strange red floors that deal damage when stepped on.
These red floors are hazardous areas and are primarily found in the second biome of Returnal, the Crimson Wastes. That said, they can appear in other biomes, and they generally either block players progression or simply make it harder for Selene to maneuver around. Thankfully, the damage from these sources can be negated with the Promethean Insulators.
The Promethean Insulators are one of nine Xenotech Devices that Selene can use get permanent upgrades, and it is also one of the only ones that can be missed entirely. To get these, players will have to work their way to Act 2 and open the portal to the Fractured Wastes, meaning until that point these red floors simply need to be ignored. Once in the Fractured Wastes, continue until coming across a vault door for the Hadal Vault.
This vault is unique in that it requires three keys to open. Branching off from this main area, players will notice four doors leading in different directions. Three of these doors are marked as Main Paths and will each eventually lead to a Hadal Vault Key, but the fourth door is a Side Path and is locked. If players have an Atropian Key, they can unlock this door and reveal the path to the Promethean Insulators. Dodge the lasers and other hazards in this room in order to make it to the other side and claim this optional permanent upgrade.
With the Promethean Insulators, players will never have to worry about these red hazardous floors again. Stepping on them still causes the floors to react to Selene's presence, but she is no longer damaged or slowed down by them in any way. This makes getting to certain areas possible and is also required if players want to see the secret ending of Returnal.
Returnal is available now on PS5.