Took from Useful/Recommended Class Builds on AE forum:
Notes/How to use: Here it is, the new guardian class! As you can see, physically it's gotten a large boost of power. You're going to always want to keep the skill Keen running. This helpful increase of critical hit chance will be of great use. Not only that, but it will also stun your opponent sometimes. If using Wizard enhancements, use Guardian Light after using Keen followed by a Guardian Rage. If not, just stick to spamming Guardian Rage
Class: Fighter / Wizard
Helm: Fighter / Wizard
Notes/How to use: Guardian doesn't have bad dexterity so if you want to throw in a little thief enhancement for dodging, feel free to. Anyway, begin by using the skill Guardian Light. If you use this without using Keen it will boost your defense against oncoming attacks. Use Keen once after using Guardian Light for stat boosts. Keep that going every time it recharges. Use Guardian Rage to cause damage. When your opponent is getting to be low on HP start using the strategy listed under the Physical type.
Weapon: Fighter / Thief