It was pretty fun up until the campaign ended. After that you only have 2 things to do.
1. Do the same daily event over and over again. There's no point really after the first time since you don't obtain anything after that. It's really not fun considering the limited decks most people have.
2. Do the weekly event. Which consists of you battling 25 people instead of 3. And most of which are probably going to be offline, so you won't finish the battle for a day at least. Really unfun, can take forever to complete. If I like the game then why would I want to play a part of it that forces you to be idle until someone feels like moving.
Basically after the campaign, there's no reason to log in more than once a day for about 10 minutes for the daily. The weekly takes too long and is too boring because no one is going to finish the battle with you, they give you an alert when your opponent makes their move and you can make yours at your leisure. After you do the daily, you're done unless someone actually made a move in the weekly. In which case you get to spend maybe another minute playing. And then you log off and play something else until you feel like checking for the weekly again. Rinse repeat, except you're only doing the weekly.
There's nothing to do.
The rate that you acquire new troops is also extremely sluggish. You're confined to using your starter deck until you can afford to purchase several of the card packs, which could take months.
Real shame, has a lot of potential.