Complex sentence: Though the wound to Tom's face was across blood rich tissue and covered him in his own blood, had the bullet gone through the mouth or the soft tissue of the neck it would have likely struck a major vessel and caused him to bleed to death.
Split into simpler sentences: Though the wound to Tom's face was across blood rich tissue and covered him in his own blood. Had the bullet gone through the mouth or the soft tissue of the neck it would have likely struck a major vessel and caused him to bleed to death.