In life, the Skeletal Swordmaster met no equal with a blade. Even in death, he has retained much of his renowned skill. If the Swordmaster turns your blade, he will gain a quick strike that does not count as his official attack.
This makes the Swordmaster a tricky foe, and amplifies the severity of a poor attack roll. Considering he has two life points, it may be wise to discard a "Sacred" loot card to gain an edge in the fight.