I love Promenade of Malice! With the amount of unit kill, discard, and milling Dark Elves do already, you're bound to Malice out an opponent's card from play more than once a game. My favorite part, though, is that it gives Dark Elves a potentially repeatable way to take down opposing supports that frustrate their strategies without reliance on neutral or allied cards or effects (which are often non-inherently repeatable).* Egathrond only adds to the malicious revelry by blowing up developments that may very well be the opponent's "extra" copy of something annoying he has in play.

But, as far as I can recall, isn't Promenade of Malice the first card in the game that enables players to remove a quest from play? Even if not, I think this "addition" to the list of quest removal comes just in time to prepare for the BQ cycle.

Is there anything I mentioned above that is illegal? The way I read the card, it can do all these things. Share your thoughts please.

* This is also the reason I like the Raiding Camps Chaos Quest from the first Capital Cycle pack so much.

Yes, it is. One of the other members sent that question in to Lukas and the answer was that it can destroy quests and even legends. It's in the City of Winter Spoiler thread further down the page.