At first I thought this was a random copy and paste AFK rpg, however the battle system is rather unique. I've never played an AFK rpg that utilizes a chess-like battle system. The sound is mediocre, the voice acting is good, and the graphics aren't bad. The characters however do not have character illustrations, which kind of takes away their value. They only have character avatars that do only one move animation and that's it. The auto-battle AI need work, sometimes a character won't even move and attack a blank space the entire time (wasting their ulti too). The packages are actually worth it most of the time, I suggest you get the first top up package because it gives you the best tank in the game (you'll need her, trust me). They are very generous with summons, infact they have a beginner's re-roll summon and you can re-roll up to 20 times. I suggest you try to roll for Robin Hood (best damage unit), Adonis (best support), or Vivienne (she's the tank you can get in the first top up package if you don't get her in the re-roll). The storyline is okay but it's kind of boring imo, you don't really need to pay attention to the story but I would pay attention to the tutorials.
Anyways, I say this game is pretty decent and it's worth a try if you need a game to kill some time.