Skills for a Pure INT Cleric

Max ironheart, thats a keeper, and max arrow/cyclone. Wellspring is optional, but if you're really good and can watch pre-emptively in AoE parties and FBs, you don't need wellspring. It's not really necessary because eventually you'll just grind monsters that you can 3-shot monsters using your two basic attack spells with metal mastery and flight skill to increase efficiency of grinding. Make sure to get a lot of +magic and +mp recovery on your equipment as its your most important stat, then wood resistance until lvl 54.

Essentially, you don't want to kill any monsters that can touch you until level 49, and if they do, its a magic monster which does measily damage. Up your magic shell skill when you feel like it, but not necessary to max it.

First twenty levels, you want to grab as much PDef as you can because most monsters are physical damage. Just play normally, your build barely even matters. Eventually, when you start questing in Archosaur, you can only do about 2 spells, then pureheart yourself, and then continue your arrow/cyclone cycle. Hopefully you stock up on 300+ potions when you decide to do a full sweep of the zone for quests (basically the mines and around Orchid Temple), it takes that much mana. Unless you have cash shop money, you should do that until you can save up for your first silver charm. Try to purchase your silver charm as soon as possible, as its the most money-efficient way to grind. After that, you can do anything for xp, including wood monster grinds or FBs for experience (you'll experience a stall of quests around lv35). At around lv39 with a two star weapon, I was three-shotting the Cloud Vipions so it because really easy by then. Keep killing them for a while (me personally I had to grind them until level 49 when I was able to use my 2 star glaive to 4 shot the Evolved Vipions).

However, you'll be probably grinding there for a long time until you can find, at least on on the PvP server, a decent weapon or upgrade to go to the next area. But by then when you want to leave (around lvl 43 because it becomes green), you begin your monotonous AoE grind parties. Try to be friendly, create chatrooms for AoE lv44 parties, or use telecoustics to advertise. You can then get a lot of xp, but money becomes a problem. Don't try to get a profession up, sell your mats overnight, and you should be good to go in the money department from all your Vipion grinding. You should depend on your guild for pretty much everything (craft wise), and your guild will in return will get a super cleric.

At the end, around lvl 54, just do AoE grinding and dungeons. You can't really expect to do anything else because thats what you'll be doing for the rest of the game.