I've played this deck occasionally and it's surprisingly good against a lot of decks that don't expect any kind of Harsh Rule to come up. I think it has a decent matchup versus a lot of decks (Onis, Stonescar Dragons, Combrei Aggro, Elysian Tempo). The Xenan Cultists is a bit worse though. The idea is just to remove everything from your opponent and then abuse Echo and high-power cards to keep gaining value.
Ghar, besides somewhat comboing with Fall Short, is very satisfying. I have hit a Scorpion Wasp after it just got Immortalized and it was so satisfying.