Prawnsuit, the correct materials to make a bio/ nuclear reactor, water treatment plant, fabricator, multipurpose room and a hatch. Make sure to bring appropriate sustenance, a beacon, sea glide and stasis rifle along with some fuel for the reactor you have chosen to build. You should also go to the floating island and bring down lantern fruits for food, kelp from the kelp forest for crafting, blood kelp for crafting and gel sacks for crafting. The entrance I recommend is blood kelp forest (not trench) as you can Lifepod 2, blood kelp and uranite easily. I consider it the best entrance with the only downside being both biomes have a ghost so you need to be careful.
Ranking of the entrances:
4. Koosh: sandwiched in between two biomes filled with reapers and being filled with Bonesharks and ampeels by itself you are just about guaranteed to have a run in with a reaper, it’s also the furthest away from the ILZ 0/10
3. Grand/ sparse reef: you probably won’t get your cyclops in and Warpers will harass you in any other vehicle, + you have to go through a gauntlet of crabsquids to actually get in, it’s also the second furthest from the ILZ
2. Blood kelp trench: pretty close to the dunes so you need to be quick, you’ll have a hard time fitting a cyclops down there but it is the best way to get straight into the belly of the lost river + it’s pretty close to the ILZ
1. northern blood kelp zone: easiest route to the ILZ, tied with koosh for easiest cyclops entrance, however this route is far away from the ghost in the NBKZ, close to Lifepod 2 and close to a very good wreckage in the floating islands that has multiple prawn suit arms and cyclops engine bits, while it is in between the mountains and dunes it’s on the sides of them that have basically no reapers. This biome also has the important resource of blood kelp.