The underground city is three full and four full. What are these industrial maps and dimensional gates?

Sanman, Silverstone Meteorite, Invitation Letter, Challenge Letter (Time and Space)

Four fullness, time and space (silver meteorite, invitation letter, challenge book, endless eternity)

Sanman, burning meteorite, invitation letter, challenge letter (industrial zone)

Siman, Industrial Zone (Silver Meteorite, Invitation Letter, Challenge Book, Sorcerer's Stone)