The crusader has two forms of renewability: vanilla renewable (anything renewable in vanilla) and crusader renewable (anything renewable in the crusader mod of mini crusader mods)

Here is a list of things that become renewable in the crusader

Netherite scrap: rarely dropped by magma cubes

Diamond: rarely dropped by slimes

Netherite ingot: very rarely dropped by magma cubes

Dead bush: using weed killer on a sweet berry bush (comment if you agree it sounds wrong)

Deepslate: using a compress spell on stone

Cobbled deepslate: mined from crusader renewable deepslate