A warrior is a person habitually engaged in warfare. Warriors often form a caste or class of their own. In feudalism, the vassals essentially form a military or warrior class, even if in actual warfare, peasants may be called to fight.
Tanking and dealing enough damage to keep the enemy on the move.

Warriors need:
500 Str
700 Dex
32 Int

View Weapon Speed Requirements

Resetting your stats cost 3000 gold from a vendor.

A magician is a person skilled in the mysterious and hidden art of magic, the ability to attain objectives, acquire knowledge, or perform works of wonder using supernatural or nonrational means.
Buffs (specially monk/support mage sub-class) and freezing/poisoning/sp reduction/multi-hit-and-stun damage.

Magicians need:
30 Str
700 Mag
450 Int

View Blending Wand Information

Cancel requires 450 int.
Resetting your stats cost 3000 gold from a vendor.

A Monk is a subclass of the magician who harbours great intelligence to use spells on entire parties in a single cast. Their primary role is to keep their companions alive during group combat.

Monks need:
650 Int
700 Mag
30 Str

A person who is talented both in the arts of magic and fighting techniques.
Fast magic damage to stun. Can also be used for buffs and fencing to interrupt enemy mage casts.

Battle Mages need:
150 Str
700 Mag
450 Int

Use battle staffs, 2nd handed staffs that shoot magic and allow you to cast.
Cancel requires 450 int.
Resetting your stats cost 3000 gold from a vendor.

Someone who is an expert in range attacks(preferably in piercing range attacks)like magically throwing swords for example.
Traps for strategic advantage, long range damage to interrupt/stun mages, high DR to reduce hits taken from Warrior, effectively acting as bait/decoy for enemy tankers.

Archers need:
65 Str
500 Dex
700 Agi

An Arcane Trapper is a subclass of the Archer and uses it's intelligence and magical capabilites to place smart and powerful magical traps. It's lack of Dexterity means that using conventional bows is not effective against most classes.
Their primary role is to strategically place traps during stand-offs, using high-damage spells and utility spells such as cancellation.

Arcane Trappers need:
52 Str
450 Int
500+ Agi
300+ Mag

View more information about Traps

Agi is a stat that only archers need.
Magic traps - damage from Agility and Mag
Physical traps - damage from Agility and Strength.