All credit goes to Chromax of Gamefaqs. Images collected by Mithos. Some skills are pretty much the same for both classes, see the other classes/other types of attacks in the same class to see the pictures.
Warriors
KNIGHT
Relax: Passive (Level 20). Your MP regenerate at an increased rate.
Shield Mastery: Passive (Level 20). The defense power provided to you by shields you equip will increase.
Combo Attack: Active (Level 30). While this is active, you can chain up to 5 hits(?) against a single enemy, and use various Finish Attacks.
Panic (Sword): Active (Level 30). May blind the enemy, and can only be used with a Combo Attack, while you have a sword equipped.
Panic (Axe): Active (Level 30). May blind the enemy, and can only be used with a Combo Attack, while you have an axe equipped.
Coma (Sword): Active (Level 30). May cause the enemy to faint(?), and can only be used with a Combo Attack, while you have a sword equipped.
Coma (Axe): Active (Level 30). May cause the enemy to faint(?), and can only be used with a Combo Attack, while you have an axe equipped.
Armor Crush: Active (Level 30). Neutralize an enemy's Guard Up skill.
Shout: Active (Level 30). Lets out a shout to damage up to 6 surrounding enemies at once, but you may faint at the same time
CRUSADER
Relax: Passive (Level 20). Your MP regenerate at an increased rate.
Shield Mastery: Passive (Level 20). The defense power provided to you by shields you equip will increase.
Charge Blow: Active (Level 30). Attack with the current elemental power your weapon is charged with to hit up to 6 enemies at once. May also stun enemies.
Fire Charge (Sword): Active (Level 30). Charge your equipped sword with the power of Fire for a set time. As you activate this, up to 6 surrounding enemies will incur Fire damage.
Fire Charge (Blunt Weapon): Active (Level 30). Charge your equipped blunt weapon with the power of Fire for a set time. As you activate this, up to 6 surrounding enemies will incur Fire damage.
Ice Charge (Sword): Active (Level 30). Charge your equipped sword with the power of Ice for a set time. As you activate this, up to 6 surrounding enemies will incur Ice damage, and those enemies who aren't Ice attribute may be frozen solid.
Ice Charge (Blunt Weapon): Active (Level 30). Charge your equipped blunt weapon with the power of Ice for a set time. As you activate this, up to 6 surrounding enemies will incur Ice damage, and those enemies who aren't Ice attribute may be frozen solid.
Thunder Charge (Sword): Active (Level 30). Charge your equipped sword with the power of Thunder for a set time. As you activate this, up to 6 surrounding enemies will incur Thunder damage.
Thunder Charge (Blunt Weapon): Active (Level 30). Charge your equipped blunt weapon with the power of Thunder for a set time. As you activate this, up to 6 surrounding enemies will incur Thunder damage.
Magic Crush: Active (Level 20). Neutralize an enemy's Magic Guard Up skill.
DRAGON KNIGHT
Magic Resist: Passive (Level 20). Your resistance to all elementals of magic attack will increase.
Buster (Spear): Active (Level 30). Consecutively attack a group of enemies in front of you.
Buster (Halberd): Active (Level 30). Consecutively attack a group of enemies in front of you.
Dragon Slasher: Active (Level 30). Do a big swing with your spear, then turn and attack the enemies at a medium range. Up to 6 enemies can be hit.
Dragon Slasher: Active (Level 30). Do a big swing with your halberd, then turn and attack the enemies at a medium range. Up to 6 enemies can be hit.
Sacrifice: Active (Level 30). Sacrifice some of your HP to do direct damage to a single enemy; its defense is ignored. This is ineffective against bosses, and will not reduce your own HP below 1 (or maybe it means the bosses' HP?).
Dragon Roar: Active (Level 30). You summon a huge dragon, which roars to damage up to 15 enemies at once. At the same time, some of your HP are sacrificed and you become stunned. This can only be used when you have 50% of more of your maximum HP.
Power Crush: Active (Level 30). Neutralize an enemy's Power Up skill.
Dragon Blood: Active (Level 30). Your Attack Power increases for a set time, but your HP gradually decrease for the same. If your HP get too low, the skill automatically ceases.
ARCHER
RANGER
Thrust: Passive (Level 20). Your Movement Speed will increase.
Mortal Blow: Passive (Level 20). A certain chance of attacking an enemy when it gets too close with a certain chance of instantly killing an enemy with less than 50% HP.
Puppet: Active (Level 20). Summon a puppet of yourself to take damage in your stead for a set time.
Fire Shot: Active (Level 30). Enchant an arrow with Fire and shoot it at an enemy. The fire bursts around the enemy and will damage others in the vicinity.
Arrow Rain: Active (Level 30). Fire many arrows into the air to pursue and attack up to 6 enemies.
Silver Hawk: Active (Level 30). Summon a silver hawk to fly around you and attack nearby enemies for a set time, or until its HP reach 0.
Strafe: Active (Level 30). Shoot 4 arrows at an enemy at once. (4 chances for Critical Shot!!!)
SNIPER
Thrust: Passive (Level 20). Your Movement Speed will increase.
Mortal Blow: Passive (Level 20). A certain chance of attacking an enemy when it gets too close with a certain chance of instantly killing an enemy with less than 50% HP.
Puppet: Active (Level 20). Summon a puppet of yourself to take damage in your stead for a set time.
Ice Shot: Active (Level 30). Enchant an arrow with Ice and shoot it at an enemy. An ice floe will erupt behind the enemy, damaging any other enemies who touch it.
Arrow Eruption: Active (Level 30). Cause many arrows to erupt from the ground to pursue and attack up to 6 enemies.
Golden Eagle: Active (Level 30). Summon a golden eagle to fly around you and attack nearby enemies for a set time, or until its HP reach 0.
Strafe: Active (Level 30). Shoot 4 arrows at an enemy at once.
MAGICIAN
MAGE (FIRE & POISON)
Partial Resistance: Passive (Level 20). Your resistance to Fire and Poison will increase.
Element Amp: Passive (Level 30). Increases the MP consumption of your Fire and Poison spells while amplifying their powers.
Explosion: Active (Level 30). Generate a large explosion around yourself to inflict Fire damage on up to 6 enemies at once.
Poison Mist: Active (Level 30). Generate a poisonous fog around yourself. Any enemies in range are afflicted and slowly lose HP.
Seal: Active (Level 30). Silence enemies in range for a set time, preventing them from casting magic. Ineffective against bosses.
Magic Booster: Active (Level 20). Increases the casting speed of your magic, but your HP and MP slowly decrease.
Magic Composition: Active (Level 30). Attack one enemy with Fire and Poison at the same time. If the enemy takes great damage and is weak to Fire or(?) Poison, it may become poisoned.
MAGE (ICE & THUNDER)
Partial Resistance: Passive (Level 20). Your resistance to Ice and Thunder will increase.
Element Amp: Passive (Level 30). Increases the MP consumption of your Ice and Thunder spells while amplifying their powers.
Ice Strike: Active (Level 30). Shoot a large number of ice blocks to hit up to 6 enemies at once. Those enemies who aren't Ice attribute will be frozen solid for a while.
Thunder Spear: Active (Level 30). Create a spear of Thunder to attack an enemy.
Seal: Active (Level 30). Silence enemies in range for a set time, preventing them from casting magic. Ineffective against bosses.
Magic Booster: Active (Level 20). Increases the casting speed of your magic, but your HP and MP slowly decrease.
Magic Composition: Active (Level 30). Attack one enemy with Ice and Thunder at the same time. If the enemy takes great damage and is weak to Ice or(?) Thunder, it may be frozen solid for a while.
PRIEST
Element Resistance: Passive (Level 20). Your resistance to all elementals of magic attack will increase.
Dispel: Passive (Level 20). Neutralizes the magical effects of enemies within range by healing the status ailments of your teammates.
Mystic Door: Active (Level 20). Create a magic portal leading to the nearest town. ((I really do not understand what it says next about the party members and how many times you can use the portal.)) If you push UP by the portal, you can move it.
Holy Symbol: Active (Level 30). For a set time, any party member within range who kills a monster will receive more Experience than normal.
Shining Ray: Active (Level 30). Unleash Holy light to hit up to 6 enemies at once. Undead and Demon enemies are particularly weak to this spell.
Doom: Active (Level 30). Changes up to 6 enemies into ((it says "Denden" in katakana... maybe it's the proper name of an enemy in the game?)), reducing their Attack Power and Movement Speed. The higher your Skill Level, the stronger the enemies you'll be able to transform. Ineffective against bosses.
Summon Dragon: Active (Level 30). Summons a sacred dragon to attack enemies. The higher your Skill Level, the stronger the dragon you'll be able to summon.
THIEF
THEIF MASTER
Shield Mastery: Passive (Level 20). The defense power provided to you by shields you equip will increase.
Chakra: Active (Level 30). Gradually expend MP to recover HP. If you move or attack, the skill ceases.
Assaulter: Active (Level 30). Speedily and fiercely attack an enemy, who may faint.
Pickpocket: Active (Level 20). Enemies will drop Mesos when you attack them for a set time. The amount of Mesos depends on the damage done and your Skill Level.
Thieves: Active (Level 30). Summon associates to attack up to 6 enemies around you.
Meso Guard: Active (Level 20). Expend Mesos to reduce the amount of physical attack damage you take for a set time.
Meso Explosion: Active (Level 30). Drop Mesos to the ground and they'll explode, hitting up to 6 enemies at once.
HERMIT
Alchemist: Passive (Level 20). The effectiveness of various healing items and the duration of ability changing items you use will increase. But Elixir items' effects will not increase.
Meso Up: Passive (Level 20). The amount of Mesos dropped by monsters killed by party members in range is increased.
Shadow Partner: Active (Level 30). Summon a shadow partner that mimics your actions for a set time, or until its HP reach 0.
Shadow Web: Active (Level 30). Turn your own shadow into a spider web to capture an enemy, preventing it from being able to move, cast magic, and use skills.
Shadow Meso: Active (Level 30). Throw Mesos to attack an enemy; they get expended in place of MP. This attack ignores the enemy's Guard Up and Magic Guard Up effects.
Avenger: Active (Level 30). Expend many MP and Shuriken in order to create a huge shuriken to throw at an enemy. The shuriken will rip through the enemy and keep going, able to hit up to 6 enemies.
Flash Jump: Active (Level 20). Execute a second jump while already in the air. The higher your Skill Level, the further the second jump will take you.
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