You seem to be misinterpreting how the Shadow Illusion ability of the Shadowcraft Mage PrC works.
Yes, it allows the caster to alter a persistent image spell, for example, from a figment into a semi-real shadow effect.
But you can only use this ability to reproduce specific spell effects.
Yes, it allows the caster to alter a persistent image spell, for example, from a figment into a semi-real shadow effect.
But you can only use this ability to reproduce specific spell effects.
A shadowcraft mage can use the altered spell to mimic any sorceror or wizard conjuration (summoning), conjuration (creation), or evocation spell at least one level lower than the illusion spell. The altered spell functions identically to the shadow conjuration or shadow evocation spell, except that the spell's strength equals 10% per level of the figment spell used.