I think the wording could be improved but I can't really think how! The final bit should be changed to "This loses 1 Durability"
(Like (Sword of Justice))
"Deal 1 damage to a minion. This loses 1 Durability." is enough I think. Alternatively, it could be limited to "an enemy minion" if you don't want it as an enabler for enraged minions etc?