Sometimes you will struggle to make the Advanced Classes you need to MVP before you finish the run. Here is some advice for these setups.

The Classes that run Overload can get to the 3rd Boss without needing to be activated, just keep them as Rockie (1P Upgrade available from the Talent Menu) until you can get the 3 needed and go straight to the Advanced Class if you struggle to get it before the end of the run.

For those that don't use Overload, Rockie can get to the 2nd Boss before needing to be swapped out for their Base Class, so hold onto any of them you get until then, as there is a chance you will be able to get the 3 need to Advanced Class them by then.

For the Melee Classes, put most of the Enhancements you get into them, in order to keep them alive for the Hell Waves/Bosses, since all their skills are focused on dealing damage. I normally get them to 100 Defense minimum before any buffs take effect in battle, and I get the Healer and Buffer to 50 Defense minimum also. The Tank doesn't need any of the Defense Enhancements as he gets a lot from him Abilities Passives, and he only needs 2100 HP minimum.

Tank: Fighter/Veteran
Frozen Aura
Shield of Frost King EX (Frozen Shield 3 + Arctic Domain 3)
Crystal Defense

Healer: Priest/Apostle
Gentle Rainfall (Class Skill)
Healing Scatter Shot
Stronghold Healing EX (Healing 3 + Defense Enhancement 3)

Buffer: Idol/Star
Speed Boost
Heavenly Song (Class Skill)
Stronghold Healing EX (Healing 3 + Defense Enhancement 3)

Have Idol/Star running Defense Enhancement while Priest/Apostle uses Healing until you get your first Stronghold Healing EX (make sure you can re-equip a Level 1 minimum Defense Enhancement to Idol/Star before making it to maximise defense effects).

Use Icy Multishot and Frozen Strike until you can make their corresponding EX Skills. His attack speed is inherently fast, and Shadow Dagger makes it quicker allowing those skills to trigger constantly.

Skills:
Shadow Dagger (Class Skill)
Ice Scatter EX (Icy Multishot 3 + Ice Elemental Thrust 3)
Frost Blast EX (Inertial Strike 3 + Frozen Strike 3)

Use Icy Multishot until you can make the EX Skill.

Skills:
Gentle Breeze Leaves (Class Skill)
Overload
Ice Scatter EX (Ice Elemental Thrust 3 + Icy Multishot 3)

Use Magic Bullet Scatter and Flame Burst until you can make the corresponding EX Skills.

Skills:
Flame Scatter EX (Burning Fireball 3 + Magic Bullet Scatter 3)
Flame Burst EX (Burning Fireball 3 + Flame Burst 3)
Frozen Burst

Use Triple Slash until you can make Flame Streaks so his Class Skill triggers very frequently.

Skills:
Flame Whirlwind Slash (Class Skill)
Flame Streaks (Triple Slash 3 + Fiery Strike 3)
Overload

Skills:
Bomb Throw (Class Skill)
Melting Shot
Overload

He starts off weak, but once you get all 3 Skills to Level 3, along with Buffers Speed Boost to Level 3, he is a beast.

Skills:
Blaster (Class Skill)
Fiery Strike
Overload

Use Icy Multishot until you can make the EX Skill.

Skills:
Frost Charge (Class Skill)
Ice Scatter EX (Ice Elemental Thrust 3 + Icy Multishot 3)
Overload

I set her up as a Melee for the sake of her Ability, so that all the enemies she fights including Bosses, are always affected by it, they wont ever be out of range, and the extra Broken Armor stacks just help her melt even the Final Boss quickly.

Skills:
Lightning Chain (Class Skill)
Thunder Shoot EX (Explosive Shot 3 + Thunder Orb)
Thunder Slash EX (Fiery Strike 3 + Thunder Orb)

Anger is a Class you can make from combining Mage + Boxer once you've beaten Expert or Hell difficulty 3 times.
She's a Melee Magic Class that relies on Fire attacks for Buffs from her Ability.

Skills:
Blaster (Boxer Class Skill)
Overload
Fiery Spiral

I cleared this with Tank (Advanced), Healer (Advanced), Mage (Base), Anger.