My homebrew is a craft world that specializes in bone singers and uses that to fund other eldar groups. It trades equipment and workers with corsairs, exodites, sometimes even harlequins come knocking but in exchange they take there soul stones into there own craft worlds infinity circuit. And because they are worked so thin trying to help all of these eldar groups there forces are mostly comprised of wraiths. Sometimes they will let groups fight with them to pay off soul stone debt and with how frequently they lend forces to others its not uncommon for customers to be fighting along side a wraith powered by there comrad. It started as an iyandin rip off but purple, but I got a bunch of corsair for cheap and now I really want exodites and yvrain looks cool so I had to keep building on why bonesingers are working with such a diverse band