You might have dropped the ball on duskblade

Lethality isn't really a problem right now. For what it is worth, Lethality is good in the early game. But duskblade? Duskblade just guarantee a near one shot for any champion who can disappear in a fight intermittently.

If you are going to leave Duskblade as it is, give us some trinkets specifically designed to counter the thing. Because it will shut down any wards the user walks near.

The only way to counter this right now is to drop control wards in the middle of a team fight. So placing a control ward in the middle of a fight doesn't really do anything unless your working with a team that will have one place a ward to cancle the passive. And the others place wards in a circle to keep him from disappearing.

The less reasonable counter is to have everyone stack armor. Which would make ADCs worthless because of how they are designed. You'd need to re-balance the entire cast.