Unlike a lot of RPGs, this game has no classes, and the skills are not linked to those specific classes. In this game, you build the character you want to be, of cuorse you require certain stats for each skill, but you can still mix and match. Here's a skill list without the requirements:

Sword Mastery / Blunt Weapon Mastery / Magic Mastery / Bow Mastery

Sword Plus  (Damage with sword constantly raised) / Slash Attack / Critical Buff // Fire Slash / Lightning Slash / Ice Slash

Heal / Power Up / Defense Buff // Fire / Lightning / Ice

Hammer Plus / EarthQuake / Critical Smash // Fire Swing / Lightning Swing / Ice Swing

Bow Plus / Arrow Rain / HeadShot // Fire Arrow / Lightning Arrow / Ice Arrow

Here is a preview image of the skill icons.