well to me the remove "X" is the cost of the minion, why should i pay it twice? (plus the 2 of the event) it's just insane.
To me is a "decent" event that let you pull a minion from deck paying 2 more, or discard a follower.
I don't think it's mean to pay double(even if you can pull any wraith minion, who can be cheaper than a nazgul, but still a 1 cost minion would just eat 4 twilight away.. too much IMHO)
Given that the card is not a common, it seems pretty fairy as a cost to me, the way i interpreted it.
I'm curious to know what other people think.