The last Korean MMO I played was the super-grindy Rising Force Online...it was pretty fun for the time, and it was much like Aion (which came after it) in that it was predominantly faction v. faction PVP as its main feature, with PVE on the side to support PVP prowess.
I actually didn't mind it for its grind (it was the stereotypical "Korean grinder")--I was so used to FFXI's grind that I did pretty well at it. The thing that turned me off specifically was the crafting system...they used a system similar to the FFXIV "multiple-materia-meld-and-chance-to-break" to gain high-powered end-game items.
Because of the dynamic of the game, everyone focused on this RNG risk-loss crafting, as it meant such a difference in end-game PVP. As such, the game eventually revolved around whomever had either the biggest player-guild (and thus resource pool) or greatest number of bots to farm PVE to get materials to craft. Because bots were more accessible and meant having not to share with others, botting and multi-boxing/one-to-many-peer-UI-commands became rampant and whole teams of bots would be seen farming the big end-game bosses. It seemed like the gambling/crafting game became filler for any "end-game content" as it was all one-in-the-same.
The other frustrating aspect was the lack of support from the parent company. CCR would update the Korean client often but would drag their feet in sending the localised code to Codemasters (the UK-licensed publisher for the NA/EU region) which resulted in bugs and exploits sitting around unanswered for weeks to months...it got to the point where Codemasters just simply gave up and discontinued servicing the game. For whatever reason, Level UP games (the publishers in the Philippine Islands and Brazil) didn't have such a bad experience and kept up service in those areas.
Anyhow, when the game closed down for NA/EU, I was saddened a bit, as it was really special (being absolute cut-throat open-world non-consensual PVP everywhere) but due to the above, I didn't exactly mourn its end. Due to the bad experience, I was hesitant to try Aion (which most RFO players went onto instead of going to the Korean RFO servers)--and even balked a bit when FFXIV introduced a similar "multiple-materia-blow-up" crafting system in 1.23. :p Oh well. :p
