The dwarven shield "Rolf's Saviour" is an artifact in ADOM. It is a decent shield that grants resistance to fire, cold and poison. If the shield is wielded with Rolf's Companion, it boosts the to-hit and damage of the axe by +10 each... but only if the PC wields the axe in their left hand and the shield in the right. Whilst the shield is not always generated even for PCs that satisfy a particular requirement, it cannot be obtained in any other way either; thus giving the artifact the confusing status of being 'guaranteed' even though most PCs will never see it.