By the end of this guide you will be able to take a Thief from the level 10 job advancement to level 30. You will know which weapon type to pick, which skills to raise first and why, which monsters are worth hunting, and how to choose between Assassin and Bandit. The guide covers MapleStory Classic World (Classic World from here), Nexon's recreation of pre-Big Bang MapleStory that runs inside the Global MapleStory (GMS) client. Numbers come from mapleclassic.wiki unless a section names Nexon. Where the sources are silent, the guide says so instead of guessing.
Becoming a Thief at level 10
Per Nexon's FAQ, Classic World characters are created fresh on Maple Island, which covers levels 1 to 10. Per mapleclassic.wiki, Victoria Island is level 10 and up. There are four job branches (Warrior, Magician, Bowman and Thief) plus Beginner, and only first and second job advancement exist at launch. The Thief advances at level 10 in Kerning City, and its primary stat is LUK (the stat your damage mainly depends on).
- Reach level 10 on Maple Island. EXP (experience points) is what fills your level bar. You should now see 10 as your level in the status window.
- Travel to Victoria Island, then to Kerning City, one of its six towns (Henesys, Ellinia, Perion, Kerning City, Lith Harbor and Sleepywood). The sources we use do not record the route, so use the in-game map. You should now see the map name Kerning City on screen.
- Speak to the Thief job instructor in town. The sources do not list the NPC's name or any quest text, so read the dialogue in game. You should now see your class change from Beginner to Thief.
- Open the skill window. You should now see six skills: Dark Sight, Disorder, Double Stab, Keen Eyes, Lucky Seven and Nimble Body.
Three systems open around the same time, per Nexon's Founder's Access release notes. Crafting starts at level 10. Citizenship starts at level 12, and Henesys and Kerning City residents get shop, cab and storage perks, which matters because Kerning City is your home town. The Kerning City Party Quest starts at level 21 and is where King Slime lives. Nexon also states that the maximum level is 100, but this guide stops at 30 because that is where second job begins.
Thief skills: what the data lists
The table below is the wiki's first-job list. MP (mana points) costs are shown as a range because the wiki lists two figures per skill; it does not say which end belongs to level 1. Blank cells mean the wiki records no value there, not zero.
| Skill | Max level | MP cost | Damage % | Hits | Targets | Requires |
|---|
| Disorder | 20 | 5 to 10 | 100 | 1 | 1 | None |
| Double Stab | 20 | 8 to 16 | 160 | 2 | 1 | None |
| Lucky Seven | 20 | 8 to 16 | 120 | 1 | 1 | None |
| Dark Sight | 20 | Highest range of the six; read it in game | | | | Disorder Lv 3 |
| Nimble Body | 15 | | | | | None |
| Keen Eyes | 15 | | | | | Nimble Body Lv 3 |
Three things stand out. First, Double Stab and Lucky Seven cost the same listed MP (8 to 16), but Double Stab lists 160 percent over 2 hits and Lucky Seven lists 120 percent over 1 hit. The table does not say whether 160 is per hit or in total, so do not treat the gap as a measured damage difference. Second, Disorder is the cheapest skill on the list at 5 to 10 MP, and level 3 of it unlocks Dark Sight. Dark Sight carries the most expensive MP range of the six. Third, Nimble Body and Keen Eyes list no MP cost, damage or element, and the wiki table gives no effect text for them. Read their descriptions in game before spending points.
Stars or daggers: choosing a weapon
The fact sheet lists two weapon types for a first-job Thief: Dagger and Claw. Claw is the throwing-star weapon type, which is why players say stars. The choice matters because the two second jobs split the weapons between them:
| Class | Tier | Weapon | Primary stat |
|---|
| Thief | 1 | Dagger, Claw | LUK |
| Assassin | 2 | Claw | LUK |
| Bandit | 2 | Dagger | LUK |
Both second jobs use LUK as the primary stat, so your stat plan does not change. Only your weapon does. Here is how to decide:
- Pick the second job you lean toward, using the comparison later in this guide.
- Equip the matching weapon type for the whole 10 to 30 stretch. An Assassin uses Claw and a Bandit uses Dagger, so the matching weapon means no switch at level 30.
- Check that your first attack skill works with the weapon you hold. The fact sheet does not list weapon requirements per skill, so the skill description in game is the check. You should now see the skill become usable without an error message.
What the sources do not give us: weapon attack values, accuracy differences, attack speed, or the cost of throwing-star ammunition. Without those numbers, no claim that one weapon is stronger at levels 10 to 30 can be backed up here. For why a character misses at all, see the published guide on Accuracy and Avoidability. For how the four stats work, see the published STR, DEX, INT and LUK guide.
Skill order for levels 10 to 30
The fact sheet does not list how many SP (skill points) you earn per level, so this order is a priority list, not a point count. The build condition is solo grinding from level 10 to 30, and each step carries its reason.
- Raise one attack skill first. Double Stab or Lucky Seven, whichever works with your weapon. Reason: these are the two listed skills that spend MP to deal damage with a stated percentage, 160 for Double Stab and 120 for Lucky Seven, and both cost 8 to 16 MP.
- Put 3 points into Disorder. Reason: it is the cheapest listed skill at 5 to 10 MP, and level 3 is the requirement for Dark Sight. Leave Dark Sight for later, because its MP range is the heaviest on the list and your MP pool is not in the fact sheet.
- Put 3 points into Nimble Body. Reason: Keen Eyes needs Nimble Body at level 3. Nimble Body's own maximum is 15 and its effect text is not in our sources.
- Return to your attack skill until points run out or the skill reaches its maximum of 20.
If your MP bar empties quickly, the usual cause is casting a costlier skill on weak monsters. Potion spending is covered in the published Potions Ranked guide.
Where to train from level 10 to 30
The wiki's monster table has 28 monsters in the 10 to 30 band. We rank them by EXP per HP (hit points), our own derived figure: the EXP a monster gives divided by the HP you must remove. Jr. Necki, for example, gives 39 EXP for 272 HP, which is 0.143. Ribbon Pig gives 19 EXP for 172 HP, which is 0.11. The table shows the ten highest-ranked.
| Rank | Monster | Level | HP | EXP | EXP/HP | Weak to |
|---|
| 1 | Jr. Necki | 21 | 272 | 39 | 0.143 | None listed |
| 2 | Stirge | 20 | 296 | 37 | 0.125 | None listed |
| 3 | Octopus | 12 | 191 | 23 | 0.12 | Lightning |
| 4 | Green Mushroom | 14 | 233 | 26 | 0.112 | None |
| 5 | Ribbon Pig | 10 | 172 | 19 | 0.11 | None listed |
| 6 | Bubbling | 15 | 259 | 28 | 0.108 | Lightning |
| 7 | Orange Mushroom | 8 | 142 | 15 | 0.106 | None listed |
| 8 | Zombie Mushroom | 24 | 436 | 45 | 0.103 | Holy |
| 9 | Blue Mushroom | 19 | 342 | 35 | 0.102 | None listed |
| 10 | Horny Mushroom | 22 | 403 | 41 | 0.102 | None listed |
Read the table as a comparison of effort, not a promise of speed. The ratio ignores how fast monsters respawn, how hard they hit, what they drop, and how far you walk between them. None of those figures is recorded in our sources. The sources also give no recommended player level for each monster, so the bands below follow monster level only. The elemental weaknesses (Lightning for Octopus and Bubbling, Holy for Zombie Mushroom) do not help a first-job Thief, because the skills in the table above list no element.
Levels 10 to 15
Ribbon Pig (level 10), Orange Mushroom (level 8), Octopus (level 12), Green Mushroom (level 14) and Bubbling (level 15) fill this band. Per the wiki's monster counts, these maps sit around Kerning City:
Octopus ranks third at 0.12, ahead of Ribbon Pig at 0.11, so the construction-site maps are the stronger pick on this data. Bubbling has the largest count in the ranked data: 64 on Line 1 (Area 1), plus 9 on B1 (Subway Depot). A crowded map means fewer steps between targets, but the sources do not say how fast monsters return.
Levels 19 to 22
Four monsters in this band rank well. Blue Mushroom (level 19) has 16 on The Blue Mushroom Forest, 12 on The Breathing Rock, 12 on The Entrance of Golem's Temple and 11 on The Road to the Dungeon. Stirge (level 20) has 38 on Dangerous Steam, 35 on Dark Cave and 38 on Transfer Area. Jr. Necki (level 21) has 27 on Dangerous Croko I, 19 on The Swamp of Despair III and 17 on The Swamp of Despair II. Horny Mushroom (level 22) has 41 on Ant Tunnel IV, 38 on Ant Tunnel III and 24 on 1st Accompaniment (Bonus). Jr. Necki and Stirge are the two top-ranked monsters in the whole band, which makes them the first candidates once you reach their level.
Level 24 and beyond
Zombie Mushroom is the highest-level monster in the ranked table, at level 24 with 436 HP and 45 EXP. Ant Tunnel III holds 61 of them, Ant Tunnel II holds 32 and Deep Ant Tunnel I holds 29. Its ratio of 0.103 is lower than Jr. Necki's 0.143, so the extra EXP per kill comes with proportionally more HP to cut through. The ranked table has no monster above level 24, so the sources do not name a clear target for the last stretch before level 30. Keep hunting the monsters above, or use the Kerning City Party Quest, which opens at level 21 per Nexon.
If a map is crowded, change channel (click the channel button or press the channel key). Monsters, drops and quests are identical on every channel; only the players differ, per Nexon's FAQ. Party members must be on the same channel. If you die while training, the published Dying in Classic World guide covers EXP loss.
Assassin or Bandit at level 30
Both second jobs are taken in Kerning City at level 30, per the wiki. The skills below are what each branch lists. Third job is not available at launch, so these two lists are the end of the Thief line for now.
| Job | Skill | Max level | MP cost | Damage % | Hits | Requires |
|---|
| Assassin | Claw Mastery | 20 | | | | None |
| Assassin | Claw Booster | 20 | 30 to 10 | | | Claw Mastery Lv 5 |
| Assassin | Critical Throw | 30 | | | | Claw Mastery Lv 3 |
| Assassin | Critical Recovery | 20 | | | | None |
| Assassin | Drain | 30 | 14 to 28 | 240 | 1 | Critical Recovery Lv 3 |
| Assassin | Haste | 20 | 15 to 35 | | | None |
| Bandit | Dagger Mastery | 20 | | | | None |
| Bandit | Dagger Booster | 20 | 30 to 10 | | | Dagger Mastery Lv 5 |
| Bandit | Nimble Recovery | 20 | | | | None |
| Bandit | Savage Blow | 30 | 14 to 28 | 75 | 6 | None |
| Bandit | Steal | 30 | 10 to 24 | 200 | 1 | Haste Lv 5 |
| Bandit | Haste | 20 | 15 to 35 | | | None |
The two branches share a lot: a mastery and a booster, both maxing at 20 with the same MP range of 30 to 10, and the same Haste skill (max 20, MP 15 to 35). The difference is the attack skills. The Assassin's Drain lists 240 percent on 1 target in 1 hit, costing 14 to 28 MP. The Bandit's Savage Blow costs the same 14 to 28 MP and lists 75 percent over 6 hits on 1 target. The table does not say whether 75 applies to each hit or to the whole attack, so this guide does not total it. The Bandit's Steal lists 200 percent for 10 to 24 MP, and it needs Haste at level 5, so some Haste investment is the price of using it.
The choice depends on conditions, not on a single winner:
- You trained with a Claw from level 10: take Assassin, because Claw is its weapon.
- You trained with a Dagger: take Bandit, because Dagger is its weapon.
- You want an attack skill with no prerequisite: Savage Blow lists none, while Drain needs Critical Recovery at level 3.
The effects of Critical Throw, Critical Recovery and Nimble Recovery are not in the fact sheet, so this guide cannot rank them. A separate published guide covers STR Bandit, an alternative to the LUK primary stat used here.
What the sources do not tell us
- No drop rates, respawn times or spawn rates are recorded for any monster in the table.
- The wiki table lists no EXP needed per level, so we cannot say how many kills a level takes.
- First-job quest requirements, route steps from Maple Island and the NPC's name are not in our sources.
- Weapon attack, accuracy and star-ammunition costs are not listed.
Last verified 2026-10-24 against mapleclassic.wiki data synced 2026-10-24 and Nexon's Classic World FAQ.
Frequently asked
- Where do I become a Thief in Classic World?
- Per mapleclassic.wiki, the Thief first job advancement happens at level 10 in Kerning City. The sources we use do not name the NPC, so check the in-game map and dialogue.
- Should a Thief use a Claw or a Dagger?
- The first-job Thief can use both. The second jobs split them: Assassin uses Claw and Bandit uses Dagger, so match your weapon to the job you plan to take at level 30.
- What is the difference between Assassin and Bandit?
- Both take LUK as the primary stat and both advance in Kerning City at level 30. Assassin lists Drain at 240 percent in 1 hit, while Bandit lists Savage Blow at 75 percent over 6 hits and Steal at 200 percent.
- Can a Thief get a third job in Classic World?
- No. Third job advancement is not available at launch, so Assassin and Bandit are the end of the Thief line for now.
- What is the best monster for a Thief to level on from 10 to 30?
- No single answer holds for every level. By our EXP per HP ranking, Jr. Necki at level 21 leads at 0.143 and Stirge at level 20 follows at 0.125, but drop rates and respawn times are not recorded.
