Lets take a look at the magician skills(ML: Master Level, R: Requirement)

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*Improving Max MP Recovery* =Passive= (ML: 16):
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Additional points give you more MP recovered every 10 seconds. Base recovery
for MP is 3. MP recovered formula is Skills level*(Character Level/10)+3.

This skill is a MUST for all magicians. MP is needed for spells and all that
revolves around a magician is casting spells. Max this skill as fast as
possible or you will be stuck using lots of blue potions or waiting for ages
for MP to be recovered.

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*Improving Max MP Increase* =Passive=(ML: 10, R: Improving Max MP Recovery 5):
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Increases the max MP gain when you level up or when you add stats points to MP.
For every point into this skill, you get additional 2 MP when you level up and
additional 1 MP when you add stats point into MP.

This skill is extremely useful for magician. Having high MP regeneration should
be accompanied with more MP. Furthermore, Magic Guard works best with longer MP
.Although 2 additional MP when level up per point into this skill may seem
unimpressive. But at max level of 10, one level earns you 20 more MP and 10
levels add up to a whooping 200 MP more. Its advisable to max this as soon as
possible.

Level  1: 2 more AP on level up and 1 more AP on using stats point on MP
Level 10: 20 more AP on level up and 10 more AP on using stats point on MP

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*Magic Guard* (ML: 20):
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MP used: 6 (Level 1-10)
         12(level 11-20)
Partial damage to HP will be transfered to MP. For every point into this skill,
you get additional 4% damage absorbed by MP and duration of 30 seconds more.

I have heard people saying this skill makes you GOD! I didnt believe until i
tried it myself. At master level, 80% damage goes to MP and this really saves
you in precaurious situation. I once went to see Mushmom and its special attack
does 700+ damage. My poor HP is only around 400+. Without this skill, i would
have been dead, but luckily thanks to Magic Guard, i survived. Unfortunately,
this skills drains MP fast when you take damage and so should be used against
strong monsters that will kill you in 5 or less blows.

Level  1: 4% damage to MP, last for 30 seconds, 6 MP used
Level 20: 80% damage to MP, last for 600 seconds, 12 MP used
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*Magic Armor*(ML: 20, R: Magic Guard 3):
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MP used: 8 (Level 1-10)
         16(Level 11-20)
Increases weapon defence by 2 and last 20 seconds more for each additional
point into this skill.

Quite useful for magicians for early levels but not as efficient later. Since
there are other skills with higher priority to be maxed, this skill will not
begin to show its effect until late level 25+. So my advice is don’t bother
putting any point into this skill. This is because additional 40 weapon defence
isnt going to reduce a lot of damage from high level monsters and as a magician
, you should not be taking damage as much at higher levels.

Level  1: +2 weapon defence, last for 20 seconds, 8 MP used
Level 20: +40 weapon defence, last for 400 seconds, 16 MP used

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*Energy Bolt*(ML: 20):
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MP used: 7 (level 1-10)
         14(level 11-20)
Base damage of 17 at level 1 and 15% mastery. Additional 2 base damage every
additonal points into this skill. Additional 5% mastery for every 2 levels.

A basic magic attack for magician. It is not that good to put more than 1 point
into this since magic claw is a much better skill. For a start, Energy Bolt has
a lower cooldown rate so that monsters can easily recover from their knockback
to advance towards you. Secondly, this skill can be blocked by obstacles. This
is bad since as a magician, you should make use of terrain and obstacles to
avoid damage. Lastly, the basic damage reaches a maximum of 55 only. At second
job advancement, you get much better attack spells than this.

Level  1: Base dmg 17, 7 MP used, 15% mastery
Level 20: Base dmg 55, 14 MP used, 60% mastery
P.S: I believe Mastery affects the difference between maximum damage and
     minimum damage. Other class also has this mastery thing and my Warrior
     friend Aleksandr claims to have his minimum damage raised. I also found
     my damage converge as my mastery in the spells increase. Who knows can you
     please enlighten us?

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*Magic Claw*(ML: 20, R: Energy Bolt 1):
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MP used: 10(level 1-10)
         20(level 11-20)
Attacks twice with base damage of 6 at level 1 and 15% mastery. Additional 1
base damage from level 2-5. Additional 2 base damage from level 6-20.
Additional 5% mastery for every 2 levels.

A super cool attack since it attacks twice. It is considered the best magic
spell available to the magician befor 2nd job. Although its base damage reaches
a maximum of 40 only, the double attack works wonder and Energy Bolt is way
poorer in comparison. However, i do admit at low levels of Magic Claw, its
damage is really low.

Level  1: Base dmg 6, 10 MP used, 15% mastery
Level  2: Base dmg 7, 10 MP used, 15% mastery
Level  3: Base dmg 8, 10 MP used, 20% mastery
Level  4: Base dmg 9, 10 MP used, 20% mastery
Level  5: Base dmg 10, 10 MP used, 25% mastery
Level  6: Base dmg 12, 10 MP used, 25% mastery
Level  7: Base dmg 14, 10 MP used, 30% mastery
Level  8: Base dmg 16, 10 MP used, 30% mastery
Level  9: Base dmg 18, 10 MP used, 35% mastery
Level 10: Base dmg 20, 10 MP used, 35% mastery
Level 11: Base dmg 22, 20 MP used, 40% mastery
Level 12: Base dmg 24, 20 MP used, 40% mastery
Level 13: Base dmg 26, 20 MP used, 45% mastery
Level 14: Base dmg 28, 20 MP used, 45% mastery
Level 15: Base dmg 30, 20 MP used, 50% mastery
Level 16: Base dmg 32, 20 MP used, 50% mastery
Level 17: Base dmg 34, 20 MP used, 55% mastery
Level 18: Base dmg 36, 20 MP used, 55% mastery
Level 19: Base dmg 38, 20 MP used, 60% mastery
Level 20: Base dmg 40, 20 MP used, 60% mastery