Probably for good this time. The game has just too much of a "Pay to Win" model. Every month, I had to spend a week's worth of TBS money (2 weeks if you cannot solo missions) to pay for a Blessing License just so you can continue grinding. Without it, you will have to kill mobs that are like 20 levels below you. This was not the main reason though.
The main reason is the ridiculous grind. I was able to put up with the fact that I needed 3 billion exp or so to level up which was basically 2 weeks of heavy gameplay. In just 4 short levels, that has more than doubled. It seems to increase by 50% or so every level now as well. The exp wall is just too much for me and I bet many people as well. 5 billion exp needed per level and you get 2 million per fight! you can get 100 mil from daily bonuses. if you spend all your TBS points you can get 1 billion or so probably. unfortunately, no repeatable quests yet. I know several high levels that have resorted to botting as a result. The problem that this creates is that PvP is becoming more impractical and so is recruiting new mercenaries into your formation. It takes longer and longer before they are practical for you to use in any way unless you have heavily upgraded equipment. When fighting against someone with heavily upgraded lvl 141 gear in PvP, they basically hit you nearly twice as hard as you hit them. PvP balance my ass.
The second thing that killed the game for me was Spelltower. Each week, the top 50 players who apply for Spelltower on Titan can get in. Who is in the top 50 is determined by the amount of "might" that your formation has. This basically boils down to who has the highest levels and best gear. Normally this would not be a problem since it is something just meant for the best players to participate in. The problem is that you must participate if you want to be able to craft level 141 equipment. You get 1 Oriharukon if your server wins but you do not participate, but you need 20 to craft 1 piece of lvl 141 equipment.