Mineralize warrior was a spell that could only be cast on humanoids. This humanoid needed to encased in stone enclosure that resembled a coffin for an hour that the spell needed to be cast and also willing to be subjected to this spell. The first requirement made it impossible for the caster to cast this on him or herself. The caster also needed to be stronger than the target.
Mineralize warrior caused spirits of earth to become part of the subject, causing the subject to become a mineral warrior. Outward signs of these changed were that the subject looked like a petrified version of him or herself.
The subject then experienced some form of mental need to serve the caster for one year and one day. After this period of servitude, the subject was free to do whatever it wanted on its own. A caster could not create an army of mineral warriors to do its bidding, because there was a limit to how many mineral warrior servants a caster could have. This number decreased with the strength of the targets and increased with the spellcasting skill of the caster. Breaching this limit caused previously servile mineral warriors to lose their compulsion to serve the caster. However, the caster had control over whom to release and who not.
Mineralize warrior required somatic, verbal, and material components, but also the caster's own essence to cast. The material components were gems and other minerals. These stones' collective value needed to cast mineralize warrior increased with the target's strength. The same applied to the essence, which the caster needed to give up to cast the spell.