From: http://www.celtic-heroes.com/forum/viewtopic.php?f=51&t=13734#p83972
ok here it is... first few levels as you do the main quest line and grind in between pile your points 2 in dex one in hp and one in strength for the first while
continue as this untill you have 55 or so dex so that you can wear ancient lamellar, you also need to upgrade your energy whenever you start feeling energy starved, 30 should be enough
at a low level you need to save your gold, level as far as you can on your quest dagger (shoreline) then once you hit shalemont train on the skirmishers until you get a connacht dagger drop, as a rogue you should usually have double the strength as your vitality, though dexterity is also factored in at 55 for top ancient gear
because you have lower hp, avoid the connacht archers, do the quest line and focus on training on skirmishers, then the spear wilding connacht on the other side, then switch over to the ribbonswords/duellists around lvl 40 continue killing and upgrading your stats with the 3 strngth 2 vit build (dex should be 55 already)
once you tire of the ribbon swords and duellists move on through the connacht camps AVOIDING mages and archers as ranged attacks murder rogues often, kill the connacht horses as they are easy kills and grant good xp. when you have finished the shalemont questline you should be lvl 50 ish (remember to group up for harder mobs) up until this point you still should have spent 0 gold. when you think you are ready and can kill all the 1 and 2* mobs in shalemont you can move on to the northern road where you can train on the boars until you get a tusk dagger, equip this and forget the connacht one. at this point you should have the gold to buy yourself some decent armour (other players is preferable) though you could also try to get into a clan that will give you your basic disks for warden, moons suns oaks. which means you wont have to buy the ancient armour parts
keep leveling on mobs roughly your level, preferably ones with less hp because you can kill them fast with your dagger
in terms of skills, until you have an ammy of some kind you should have a 2-3 points in meditate and recuperate, a few points in bandage helps recover quickly
at a lower level, rend is a must, it speeds up the death of mobs considerably, quick strike is also a very important skill, hide is also helpful for getting through tight areas, sneaky and assasinate should not have many points in them until you have levelled up high enough to put points in them without damaging your build... thats my 2 cents, its a bit skewed and vague as it was a while ago that i did that... i leveled from 70-80 on lixers, 80-85 in the grove pre update without elixers, 85-90 without elixers in otherworld, and 90-120 on elixers lol...
if you have any questions i can answer them, i am much better at specific answers than general info- if you read through the rogue forum i post quite alot
