Armour engraved with a Rune of Fortitude grants its wearer +1 Toughness.
Armour engraved with two Runes of Fortitude grants its wearer +1 Toughness and a 5+ ward save.
Armour engraved with three Runes of Fortitude grants its wearer +1 Toughness and a 5+ ward save and, if the wearer suffers an unsaved Wound from an attack that has the Multiple Wounds special rule, roll a D6. On a roll of 2+, he only suffers 1 Wound, regardless of how many Wounds would normally be caused; on a roll of 1, he suffers the full number of Wounds.