Tiered link building uses two levels of backlinks to boost your site’s ranking....

https://scarlettsuniquedigest.yousher.com/broken-link-building-step-by-step-using-ahrefs

Tiered link building uses two levels of backlinks to boost your site’s ranking. Tier 1 links point directly to your site and carry the most value. Tier 2 links support those Tier 1 links, making them stronger and more effective