This was interesting as I found a few series of builds. I didn't realize it was just adding stats so I did research and I found quite a few on DFOSource

Berserker Section




[Hellshreder's Berserker Guide]Taste the blood, taste your fate, Swallow your pride with your hate!

Table of Contents
I. Introduction
II. Pros and Cons
III. Skill Builds
IV. Skill Descriptions
V. Tips
VI. Avatar
VII. Weapons
VIII. Sets
IX. Accessories

*Just hit CTRL + F to find what you are looking for

I. Introduction

I'll be sure to keep this short. My name is Austin, also known as Hellshreder on this Forum. Within this section, you will find my guide to be based on the blood thirsty, power hungry Berserker class! From here on out, you will find all your needs for the Berserker class and what it takes to feel the blood shed staining your skin!

II. Pros and Cons

Pros
Highest damaging Slayer Sub-Class
Only Slayer Sub-Class to use Forceful Heavy Armor Mastery
Best PvE potential of the Slayer Sub-Class
Bloody, Stylish moves
Most satisfying, blood-filled Awakening in the game
Only Class to abuse the "bleeding" Status Ailment to inflict heavy damage

Cons
Wields a Zanbato; though great for PvE, it is not ideal for PvP
If not careful, can consume HP and MP quickly
Equipment and Weapons can consume quite a fair amount of Gold
Late bloomer; Lv. 35+ is where it begins to shine

III. Skill Builds

Lv. 60 PvP Build

Lv. 60 PvE Build

IV. Skill Descriptions
Gore Cross: Gives enemies the "Bleeding" Status Ailment. When Vim and Vigor is purchased, permanently, this skill consumes HP, instead of MP. Great, but the uses eventually stack up, and you will find yourself low HP before you know. It's best to avoid spamming this move all-together until your Frenzy is a high enough level that you will receive more HP then you would losing it. In PvP, this is your go-to juggling skill.

Mountainous Wheel: If Vim and Vigor is activated, this skill becomes a semi-Y-Axis skill, which in PvP, is great advantage to have over your opponent. Mountainous Wheel is a great, downward Super Armor skill. If you have Cancel - Mountainous Wheel and using this in junction with Frenzy's X Combo, it will leave the enemy suspended in the air and allow juggling.

Diehard: Berserkers healing move when their HP is 20% or lower. Pure PvE, it's a nice skill to look at and consider maxing.

Vim and Vigor: Pretty much a REQUIRED skill for a Berserker. If you do not so much as purchase this, you are a fail-Serker and you should stop reading at this point and quit using the Berserker class. Pretty much, turns Gore Cross into a HP consuming parasite and makes Mountainous Wheel look even sexier.

Bloody Cross: A very important Passive Skill for Berserkers. The lower your health, the higher your ATK is. However, be extremely careful when managing your HP. Too low and you could end up losing your Frenzy, or worst. Dieing.

Bloodlust: This skill has a few perks you should take notice. Though the increase isn't great, it gives you a ten second boost of ATK. The second and most important , is when an Enemy is bleeding, you grab them, and you're up for, depending on your level and the Enemies DEF, 1000 DMG. Fantastic, huh? When you obtain the Cancel - Bloodlust at Lv. 30, the possibility of OTG (On the Ground) combos open up.

Derange: Screaming in agonizing pain and the sound of puking as you walk, run, or attack, your Hit Recovery, Abnormal Tolerance, ATK, Movement, and ATK speed increase for 20 seconds. However, the downfall is, your Intelligence, Physical Defense, and Magical Defense are decreased. An important buff for Berserkers. Though it doesn't feel very long, it can be a difference maker, especially in PvP.

Sacrifice: Sacrifice is an underrated skill that no one honestly gives a chance. If taken a look at, and the amount of support it offers, it makes PvE-oriented Berserkers shine when in Parties. HP regeneration, Attack Speed, Movement Speed, and a STR increase. Definitely a skill that should be looked at closer.

Frenzy: Surrounding yourself in a red aura, you can now dual wield. This is where the Berserker outshines about any Slayer Sub-Class, especially if outplayed correctly. Frenzy is a Berserkers main, and most recommended skill. This is very about every combo is opened up for a Berserker and to make him a true threat in PvP. Though it consumes HP, a fair amount of it as well, each enemy killed by you, will increase any lost HP. Further increased this level is, the less HP you lose, and the more HP you gain! It's a win-win situation!

Bloody Twister: Pulling in sucking enemies into a twister, the Berserker slashes the middle of the twister, damaging and automatically causing "Bleeding" Status Ailment on all enemies. This skill is meant only for PvE. It's uses in PvP are slim to none. A little more helpful in Team Battles, but if hit once while using the skill will cause it to interrupt immediately.

V. Tips

Unlimited healing: Each time you use a Fortune Coin when health is low and it fails, you may use Diehard to replenish lost HP, and reuse Fortune Coin until it heals you up enough times.
Never, EVER use Zanbato in PvP, unless you have proper ATK Speed Avatars.
Avoid spamming Gore Cross

VI. Avatar
Hat: 12 HP Recovery Per Min
Hair: 12 HP Recovery Per Min
Face: 4% Attack Speed
Top: Zanbato/Katana Mastery
Bottom: 150 MAX HP
Shoes: 4% Movement Speed/30 Jump Strength
Torso: 4% Attack Speed
Waist: 3% Evasion Rate
Skin: 3% Physical Damage Reduction

VII. Weapons

Lv. 25 -- Melissa
STR 302; MAG 227
STR +11
Casting Speed -2%
Miss Rate 1%
Mountainous Wheel +1
Casts an enchantment upon itself

Lv. 30 -- Diligence Sword
STR 350; MAG 263
STR +11
Casting Speed -2%
Diehard +1
Shadow Attribue
Puts the enemy in a Confused state at a 2% rate

Lv. 35 -- Shonan Custom Workshop Sword.
STR 398; MAG 299
STR +12
Casting Speed -2%
Phys. Critical Hits 1%
Miss Rate 1%
Zanbato Mastery +1
Attack Speed +5%

Lv. 40 -- Venom Slayer
STR 446; MAG 335
STR +13
Casting Speed -2%
Bloodlust +1
Overdrive +1
Puts enemy into Poisoned state at a rate of 3% upon casting

VIII. Sets

Dragon Scale Set - PvP Set (Req. Lv. 30 - 35)
HP +210
Resistance (to all attributes) +5
If HP falls to below 25%, Physical Attack Strength and Magic Attack Strength increases by 25%.

Lv. 35 Dragon Scale Coat
Evasion Rate +5%
PHY Resistance 1920
STR +10
VIT +10

Lv. 35 Dragon Scale Pants[*]Stone Curse Tolerance +10[*]PHY Resistance 1600[*]STR +10[*]VIT +10[

Lv. 30 Dragon Scale Shoulders
Pierce Tolerance +9
PHY Resistance 1120
STR +7
VIT +7

Lv. 30 Dragon Scale Belt
HP +70 - 80
MP +20 - 25
PHY Resistance 560
STR +5
VIT +5

Lv. 30 Dragon Scale Shoes
Moving Speed +6% [Regular +5%]
PHY Resistance 840
STR +5
VIT +5

Melty Blood Set - PvE/PvP Set (Req. Lv. 35 - 40)
Strength +16
Max HP +250
Raging Fury Skill +1
Frenzy Skill +1

Lv. 40 Melty Blood Breastplate
Bloodlust +1
PHY Resistance 2160
STR +11
VIT +11

Lv. 40 Melty Blood Greaves
Hit Recovery +40
PHY Resistance 1800
STR +11
VIT +11

Lv. 35 Melty Blood Shoulder
PHY Resistance 1280
STR +8
VIT +11

Lv. 35 Melty Blood Belt
Inventory Weight Limit 3kg
PHY Resistance 640
STR +10
VIT +10

Lv. 35 Melty Blood Boots
Tolerance 10
Moving Speed 5.5%
PHY Resistance 960
STR +6
VIT +6

IX. Accessories

~Coming Soon~

*Credits go to Hellshreder for making this guide.
*Credits go to Dungeon Fighter Online for some of the information on Weapons/Equipment I used.

I havn't played this game in a while (but i do know i have a zerk) it's lower level, did they really speed up the leveling process, because 23 (i think he is)- 35 seems agonizing if i went back.

very detailed guide