I finally scrabbled my way from Gold to Masters with this deck.
The primary target of Messenger Hawk is Replicator Engines. Unless you need the defense, it's best to wait until you have Crowns of Possibilities or Breeze Dancers out so you can start stacking abilities. Once you get a Replicator Engine with a nice set of abilities on it, you want to hold it (or have a way to suicide it and recover it to your hand) if possible so you can clone it with the Messenger Hawk.
Similarly, the best target for Dread is another Dread. Even if you can't attack with them, they stack abilities until they can.
While setting up one of these absurd combos, you should be using your various Necro effects to maintain board control, set up card draws with Gorgons, and bring down their life total.
Depending on the draw it can feel very aggro but is more often going to feel like a mid-range board control deck until it goes off.