Complex sentence: The Queen plans to use Yorda's body to extend her own lifespan, so Ico seeks to escape the castle with Yorda to prevent this fate from occurring, keeping her safe from the shadow-like creatures that attempt to draw her back.
Split into simpler sentences: The Queen plans to use Yorda's body to extend her own lifespan. Learning this, Ico seeks to escape the castle with Yorda, keeping her safe from the shadow-like creatures that attempt to draw her back.