For 1-15, just do quests and you should get there. HM will have to grind a bit, i suggest helltooths til lvl11 (both difficulties), and wolves/boars north of Gliter til 13~, frogs til 15.
Once you hit 15, you can pvp for a while. Enjoy it, you’ve got a long road ahead of you.
From 15-18, do quests, play with different monsters, find out what you like. If you can’t tetanus it, remember because chances are you NEVER will. The annoying monsters, over time, become even more annoying variations of themselves.
Don’t solo in AR. Don’t solo in AR. Don’t solo in AR. Do you get the message? If you’re looking for a weapon, kill skeleton soldiers, or goblin gateguards. If you’re NM, parties are cool. If you’re HM, go to map 2 and kill frogs (after doing quests).
Level 20-22 should be fairly fast due to quests. Kill whatever you want…frogs, wolves, pixies, gallus are all good targets.
Level 22-25 i can’t remember the levels exactly…but the ONLY thing you should be killing is boars/gallus south of Starfumos until you can handle bison/antelopes west of Aumeros. If you can start here at 21, start here at 21. It’s slow, slow, slow exp, but get used to it. It gets worse.
25-30 Do antelopes til they’re green. Move on to sealakels. They hit HARD but you need Spirit Cores for your quest. Get 60 of them, then find something that hurts you less. At level 27 or 28 (can’t remember which), Gigas bison/boars will be available. They are so easy it’s pathetic. Level 30 should allow you Gigas Beholders/Golems. If it’s overcrowded, you can do Gigas sealakels/frogs, but they hurt a lot. Also, don’t forget your dread quests. Silverback Goblin Hunters, Poison Mist Zombies, and Silverback Goblin Shamans drop the items to start the quest. Use this gear til lvl43.
Rapioru Maze is also a possibility for 25-30, although i never enjoyed it myself. If you go, bring potions and go at high bless or it’s slow.
Level 30 - PVP.
Do it. PVP til you’re sick of it. Til you can’t stand to see another Alliance ever. And when you hit that point, PVP some more. If you can get 1k kills do so. If you can get more, do so. This is the final frontier. There can be no looking back once you hit 31.
Don’t enter KH. Don’t enter KH. Don’t enter KH.
Pop a stone if your HM. You will never get below .08% if you pop a stone, and rarely even that low.
Level 31-32, try your luck with keuraijen big bears and spiders. They hurt. Get used to it. You can also try goblins way over to the west, but get ready for some sonic volting.
Level 33-35, your best bet is white lions. They are gloriously easy, despite rooted foot (which you will come to LOATHE by the time you hit 36), and they drop ridiculous amounts of gold. Buy exp stones with that gold, you’ll need them. Level 35 will be your slowest level to date.
Level 36 is when you can finally start in on map 2. You can start earlier if you so choose, but the fastest exp per minute is white lions. Level 36 is a rough one too, but kill goblin stonethrowers/looters til you’re blue in the face. They’re north of the first goblin camp you’ll see. You can also do D1 at 36, but have fun with farmers.
Go to FL. Go to FL. GO TO FREAKIN’ FL! This is what i’m talkin’ about. Remember those last two painful levels? Now it gets easy for a while. Take potions, don’t die, and get your glorious .2%. Even more if you’re NM (but don’t come here til 39). Hit the early rooms til 39, at which point they should turn green. Then jump the red elves entirely and move on to skeletons.
At level 40, check for quests - you get a lovely HM quest that gives you 15%. At 41, check map 2 for quest, you get an easy 10%. Kill skeletons til level 42 (the last level’s a rough one). At 42, go down to FL2 - if you have your dread set lapised up nicely, these guys should be… unbearably slow and painful. Here is when i started sucking supins and HP both. If you know of a better place to get to 43, let me know. i tried AN, too easy to die there.
This is when you start to question your worth. Those kobolts and ghosts are just as hard as ever at 43, and they give less exp. The ghosts give a solid .1 but this level will still be noticeably slower. At level 44… well… try mutants/vampires, but be prepared to suck potions. This is where i am at the moment, so i haven’t explored all options yet. If you know of a better place, let me in on the secret.
USE YOUR EPIC! It IS better than your 43. If you cannot afford mountains of lapis, use it until 50. It will get the job done. Just… avoid water monsters. god priests, vampires, sealakels…are a no.
Level 45 - if you can get in a Lan party, by all means, do it. If you have a nice guild, ask them to help you. You *can* handle the ghosts on FL3, but they come with vampires which are WAY too strong for you. Soloing, the fastest exp is vamps/mutants in FL2, though if you’re getting poor (and you will be), you might consider Futesys camp (yellow monsters). they drop a lot, require few potions, and die so easily (as all elves do).
Level 46 - Ruber Chaos is still orange and better. This IS the fastest exp you’ll get (spiders/undeads anyway, NOT vampires), BUT alone you will die. The absolute fastest “solo” exp is to get healed by an out of party oracle here. If you go alone, you’ll die quite often. Second best would be FL3, in a room with ghosts. Vamps are annoyingly long to kill, but ghosts are ridiculously easy to kill. Another option is D2, which is, in fact, faster than RC but dangerous due to Alliance. If you’re not going solo, your best bet is a fast lanhaar aoe party or a deep, deep RC aoe party.
47, D2/RC will be yellow to you. I D2, as in RC there are monsters who will debuff you extensively. If you are using the lvl45 epic (and you should be unless you have a well-lapised level 47 drop limited weapon), you will be unable to fight the succubi. Try to find a place where you can easily pull the orange skeletons without getting the succubi as well. If there are spiders nearby, even better. Don’t fight goblins if you can help it, since they stun you often. If you have access to ele lapis, stick an earth in a 47 drop limited and own the succubi too.
At 48, both NM and HM should continue in D2/RC (if you’re UM i don’t care, go own lanhaar and level fast--Shaiya powerleveling, Shaiya gold!). If you can get into a Lanhaarr party, do it. Even a random melee grind party will be fast there. Duo with a warrior and stun while he damages, or add in an oracle and damage combo. Regardless of where you level, it will be long and hard (well, actually, Lan is quite fast). If you’re NM you might consider committing suicide because you’ll do about 5 damage to Lan monsters. i might recommend suicide, actually.
According to Grizz’s post below, Hellfire monsters are rather good at 45, though i’ve tried the spot myself and was less than impressed. Your call though. in my own opinion, 45-48 should only use map 3 for quests, and even those seem to be a waste of time compared to exp you could get elsewhere in the same time.
Another possibility are leopards near the Heres relic in D-water. they are apparently beefed up and will hit hard, but they’ll give amazingly good exp for 46-48. just watch out for elves.