Corroding Arc-Knives Rafa Build
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The Corroding Arc-Knives Rafa build focuses on maximizing the damage, duration, and healing of the Arc-Knives in Borderlands 4. See the best builds, skills, weapons, and gear to use for Rafa, along with the best skill tree abilities and character playstyle.
| All Rafa Guides | |
|---|---|
| Leveling Build | Boss Farm Build |
| Arc-Knives Build | Rafa Cosmetics |
| Rafa Skill Trees | |
List of Contents
Corroding Ark-Knives Rafa Build Guide
| Jump to a Section! | |||||
|---|---|---|---|---|---|
| Skill Tree | Skill Progression | ||||
| Weapons | Enhancements | ||||
Rafa Best Skill Tree and Action Skill
| Skill Tree |  This Year's Gimmick |
|---|---|
| Action Skill: Arc-Knives | |
When using this Action Skill, Rafa stows away his guns and wields a pair of Arc-Knives. While the Ark-Knives are drawn, Rafa switches to full melee combat, slicing, dicing, and dashing his way through enemies. Reactivating the Action Skill makes Rafa perform a Blade Fury, dealing a lot of damage and ending the Skill.
Rafa Best Skills
| Jump to a Section! | ||
|---|---|---|
| Skill Tree | Skill Progression | |
| Passives | Capstone | |
Best Passive Skills
 | |||
| Skill Tree | Priority Skills | ||
|---|---|---|---|
| This Year's Gimmick |  Handshake Deal Rafa gains increased Gun Damage and Melee Damage  Midnight Oil Rafa's Action Skills deal Bonus Corrosive Damage. The longer the Skill has been active, the greater the Bonus Damage.  Dial In Whenever Rafa damages an enemy with a Melee Attack, his Melee Attacks gain Critical Hit Chance. This chance stacks, and all Stacks are removed whenever Rafa Critically Hits an enemy.  Saldar Rafa's Melee Critical Hits gain Lifesteal.  El Borracho Rafa deals increased Corrosive Damage while his Action Skill is active. The longer it has been active, the greater the bonus. This effect can stack.  Empuje Rafa gains increased Action Skill Duration.  Cruel Accrual Rafa gains increased Skill Damage with all Skills. The longer his Action Skill has been active, the greater the bonus. This effect can stack. | ||
 | |||
| Skill Tree | Priority Skills | ||
|---|---|---|---|
 Remote Agent |  Shield Barriest Overdrive Skill. Rafa gains increased Shield Recharge Rate and improved Shield Regen Delay while Overdrive is active.  Juerga Whenever Rafa Critically Hits an enemy, Action Skill Duration is restored.  Resiliencia Overdrive Skill. Rafa gains increased Damage Reduction while Overdrive is active. | ||
The best skills for the Corroding Arc-Knives Rafa Build revolve around maximizing the Arc-Knives' damage and duration, as well as giving him survivability since he will be in melee combat the entire time.
The passive skills you get from the Remote Agent Tree will give Rafa survivability, as well as Action Skill Duration whenever he performs a Critical Hit.
Recommended Skill Progression
| Recommended Skill Progression | |||
|---|---|---|---|
| Handshake Deal Rafa gains increased Gun Damage and Melee Damage Lvl 2 | Handshake Deal Rafa gains increased Gun Damage and Melee Damage Lvl 3 | Handshake Deal Rafa gains increased Gun Damage and Melee Damage Lvl 4 | Midnight Oil Rafa's Action Skills deal Bonus Corrosive Damage. The longer the Skill has been active, the greater the Bonus Damage. Lvl 5 |
| Midnight Oil Rafa's Action Skills deal Bonus Corrosive Damage. The longer the Skill has been active, the greater the Bonus Damage. Lvl 6 | Dial In Whenever Rafa damages an enemy with a Melee Attack, his Melee Attacks gain Critical Hit Chance. This chance stacks, and all Stacks are removed whenever Rafa Critically Hits an enemy. Lvl 7 | Dial In Whenever Rafa damages an enemy with a Melee Attack, his Melee Attacks gain Critical Hit Chance. This chance stacks, and all Stacks are removed whenever Rafa Critically Hits an enemy. Lvl 8 | Dial In Whenever Rafa damages an enemy with a Melee Attack, his Melee Attacks gain Critical Hit Chance. This chance stacks, and all Stacks are removed whenever Rafa Critically Hits an enemy. Lvl 9 |
| Dial In Whenever Rafa damages an enemy with a Melee Attack, his Melee Attacks gain Critical Hit Chance. This chance stacks, and all Stacks are removed whenever Rafa Critically Hits an enemy. Lvl 10 | Dial In Whenever Rafa damages an enemy with a Melee Attack, his Melee Attacks gain Critical Hit Chance. This chance stacks, and all Stacks are removed whenever Rafa Critically Hits an enemy. Lvl 11 | Saldar Rafa's Melee Critical Hits gain Lifesteal. Lvl 12 | Saldar Rafa's Melee Critical Hits gain Lifesteal. Lvl 13 |
| Saldar Rafa's Melee Critical Hits gain Lifesteal. Lvl 14 | Saldar Rafa's Melee Critical Hits gain Lifesteal. Lvl 15 | Saldar Rafa's Melee Critical Hits gain Lifesteal. Lvl 16 | Empuje Rafa gains increased Action Skill Duration. Lvl 17 |
| Empuje Rafa gains increased Action Skill Duration. Lvl 18 | Empuje Rafa gains increased Action Skill Duration. Lvl 19 | Empuje Rafa gains increased Action Skill Duration. Lvl 20 | Empuje Rafa gains increased Action Skill Duration. Lvl 21 |
| El Borracho Rafa deals increased Corrosive Damage while his Action Skill is active. The longer it has been active, the greater the bonus. This effect can stack. Lvl 22 | El Borracho Rafa deals increased Corrosive Damage while his Action Skill is active. The longer it has been active, the greater the bonus. This effect can stack. Lvl 23 | El Borracho Rafa deals increased Corrosive Damage while his Action Skill is active. The longer it has been active, the greater the bonus. This effect can stack. Lvl 24 | El Borracho Rafa deals increased Corrosive Damage while his Action Skill is active. The longer it has been active, the greater the bonus. This effect can stack. Lvl 25 |
| El Borracho Rafa deals increased Corrosive Damage while his Action Skill is active. The longer it has been active, the greater the bonus. This effect can stack. Lvl 26 | Cruel Accrual Rafa gains increased Skill Damage with all Skills. The longer his Action Skill has been active, the greater the bonus. This effect can stack. Lvl 27 | Cruel Accrual Rafa gains increased Skill Damage with all Skills. The longer his Action Skill has been active, the greater the bonus. This effect can stack. Lvl 28 | Cruel Accrual Rafa gains increased Skill Damage with all Skills. The longer his Action Skill has been active, the greater the bonus. This effect can stack. Lvl 29 |
| Cruel Accrual Rafa gains increased Skill Damage with all Skills. The longer his Action Skill has been active, the greater the bonus. This effect can stack. Lvl 30 | Cruel Accrual Rafa gains increased Skill Damage with all Skills. The longer his Action Skill has been active, the greater the bonus. This effect can stack. Lvl 31 | Shield Barriest Overdrive Skill. Rafa gains increased Shield Recharge Rate and improved Shield Regen Delay while Overdrive is active. Lvl 32 | Shield Barriest Overdrive Skill. Rafa gains increased Shield Recharge Rate and improved Shield Regen Delay while Overdrive is active. Lvl 33 |
| Shield Barriest Overdrive Skill. Rafa gains increased Shield Recharge Rate and improved Shield Regen Delay while Overdrive is active. Lvl 34 | Shield Barriest Overdrive Skill. Rafa gains increased Shield Recharge Rate and improved Shield Regen Delay while Overdrive is active. Lvl 35 | Shield Barriest Overdrive Skill. Rafa gains increased Shield Recharge Rate and improved Shield Regen Delay while Overdrive is active. Lvl 36 | Juerga Whenever Rafa Critically Hits an enemy, Action Skill Duration is restored. Lvl 37 |
| Juerga Whenever Rafa Critically Hits an enemy, Action Skill Duration is restored. Lvl 38 | Juerga Whenever Rafa Critically Hits an enemy, Action Skill Duration is restored. Lvl 39 | Juerga Whenever Rafa Critically Hits an enemy, Action Skill Duration is restored. Lvl 40 | Juerga Whenever Rafa Critically Hits an enemy, Action Skill Duration is restored. Lvl 41 |
| Resiliencia Overdrive Skill. Rafa gains increased Damage Reduction while Overdrive is active. Lvl 42 | Resiliencia Overdrive Skill. Rafa gains increased Damage Reduction while Overdrive is active. Lvl 43 | Resiliencia Overdrive Skill. Rafa gains increased Damage Reduction while Overdrive is active. Lvl 44 | Resiliencia Overdrive Skill. Rafa gains increased Damage Reduction while Overdrive is active. Lvl 45 |
| Handshake Deal Rafa gains increased Gun Damage and Melee Damage Lvl 46 | Handshake Deal Rafa gains increased Gun Damage and Melee Damage Lvl 47 | Midnight Oil Rafa's Action Skills deal Bonus Corrosive Damage. The longer the Skill has been active, the greater the Bonus Damage. Lvl 48 | Midnight Oil Rafa's Action Skills deal Bonus Corrosive Damage. The longer the Skill has been active, the greater the Bonus Damage. Lvl 49 |
| Midnight Oil Rafa's Action Skills deal Bonus Corrosive Damage. The longer the Skill has been active, the greater the Bonus Damage. Lvl 50 | |||
From Levels 1-30, your goal is to stack points in the This Year's Gimmick Tree until you unlock Altered Cabron and Galvanic Panic. Once Galvanic Panic is unlocked, with the skills leading up to it, you should reach a point where you can effectively clear encounters alone.
From Level 31 onwards, take skills that will improve your survivability and Active Skill Duration. Both Shield Barriest and Resiliencia improve your survivability while in Overdrive mode, while Juerga lets you restore Action Skill Duration whenever you perform a Critical Hit.
Rafa Best Augment
| Augment | Effects |
|---|---|
 Altered Cabron
|
• Provides Healing on kills • Gets Bonus Corrosive Damage and Movement Speed whenever Rafa heals |
Altered Cabron provides Rafa with Healing, Bonus Damage, and Movement Speed, three things that he will need whenever he has his Arc-Knives equipped. This lets him weave in and out of danger easily, while dealing a lot of damage and healing whenever he kills an enemy.
Rafa Best Capstone
 Galvanic Panic
|
||
| Tree |
This Year's Gimmick
(Branch 3) |
|
|---|---|---|
| Effect | ||
| Whenever Rafa performs a Melee Attack while Arc-Knives are active, fire an Acid STRM Glider at an enemy in his view. Acid STRM Gliders deal Corrosive Splash Damage based on the number of total Marked enemies. Additionally, killing an enemy while Arc-Knives are active restores Action Skill Duration. Activating Blade Fury causes Rafa to fire a volley of Acid STRM Gliders in front of him and end Arc-Knives. | ||
One of Rafa's weaknesses when he wields his Arc-Knives is his range, preventing him from easily attacking flying enemies. Galvanic Panic solves this problem, as performing a melee attack fires an Aciod STRM Glider at an enemy Rafa can see. This lets you target and attack nearby flying enemies, covering for his weakness.
Rafa Best Weapons
Best Manufacturer for Rafa: Any
Your Arc-Knives are your primary source of damage in this build. Done right, you will mostly be in melee combat in every encounter. The only times you will be forced to use your gun are when your Action Skill Duration runs out, or if you enter Fight For Your Life.
As such, use whatever Manufacturer you like for your weapons as long as they are capable of taking down an enemy quickly during Fight For Your Life. We recommend using Jakobs or Vladof weapons, as they can dish out a lot of damage in a short amount of time.
Best Weapon Type for Rafa: Any
As mentioned above, you will mostly be in melee combat with your Arc-Knives, so use the weapon type you are most comfortable with. We do, however, recommend Shotguns, Submachine Guns, and Assault Rifles as you will want to be in short to medium range when engaging enemies. This will let you get back into the fight faster.
Corroding Arc-Knives Best Class Mod
The Esgrimidor is the best Class Mod when using the Arc-Knives as it improves the Critical Hit Chance of your Melee Attacks. Additionally, whenever you perform a Critical Hit with Melee Attacks, you restore Action Skill Duration.
As this build maximizes the Critical Hit Chance of the Arc-Knives, you can keep refilling your Action Skill Duration, effectively staying in Arc-Knives mode during an entire fight or encounter.
How to Play the Corroding Arc-Knives Build
Activate Arc-Knives at the Start of Fights
Always start fights by pulling out your Arc-Knives. As soon as you are near an enemy, equip your Arc-Knives and perform a lunge attack to start the fight. This lets you jump into the thick of things immediately and start attacking.
Keep Moving and Attacking Everyone
While your Arc-Knives are equipped, you become vulnerable to enemies shooting from afar. As such, you have to keep moving to dodge attacks from distant enemies, as well as close the distance to nearby targets. Always be on the move to make yourself a hard target and to seek out new enemies to defeat.
Watch Out for Barrels
Barrels are capable of dealing large amounts of damage to both you and your enemies. However, as you are in melee range, accidentally hitting a barrel with your Arc-Knives can easily put you in Fight For Your Life mode.
As such, always be aware of your surroundings, and keep your distance from any exploding barrels.
Corroding Arc-Knives Rafa Build Overview
| Skills | |||||
|---|---|---|---|---|---|
| Arc-Knives |
Shield Barriest Overdrive Skill. Rafa gains increased Shield Recharge Rate and improved Shield Regen Delay while Overdrive is active.
Handshake Deal Rafa gains increased Gun Damage and Melee Damage
Midnight Oil Rafa's Action Skills deal Bonus Corrosive Damage. The longer the Skill has been active, the greater the Bonus Damage.
Juerga Whenever Rafa Critically Hits an enemy, Action Skill Duration is restored.
Dial In Whenever Rafa damages an enemy with a Melee Attack, his Melee Attacks gain Critical Hit Chance. This chance stacks, and all Stacks are removed whenever Rafa Critically Hits an enemy.
Altered Cabron Whenever Rafa kills an enemy while Arc-Knives are active, restore a portion of his Health. Whenever Rafa gains Health, deal Bonus Corrosive Damage with all attacks, and gain increased Movement Speed. This effect can stack.
Resiliencia Overdrive Skill. Rafa gains increased Damage Reduction while Overdrive is active.
Saldar Rafa's Melee Critical Hits gain Lifesteal.
El Borracho Rafa deals increased Corrosive Damage while his Action Skill is active. The longer it has been active, the greater the bonus. This effect can stack.
Empuje Rafa gains increased Action Skill Duration.
Galvanic Panic Whenever Rafa performs a Melee Attack while Arc-Knives are active, fire an Acid STRM Glider at an enemy in his view. Acid STRM Gliders deal Corrosive Splash Damage based on the number of total Marked enemies. Additionally, killing an enemy while Arc-Knives are active restores Action Skill Duration. Activating Blade Fury causes Rafa to fire a volley of Acid STRM Gliders in front of him and end Arc-Knives.
Cruel Accrual Rafa gains increased Skill Damage with all Skills. The longer his Action Skill has been active, the greater the bonus. This effect can stack.
|
||||
| Best Weapon Type | Best Manufacturer | ||||
| Any | Any | ||||
The build relies heavily on the Arc-Knives and the ability to keep them drawn. By investing in the correct skills, you can effectively stay in Arc-Knives mode infinitely as long as you have targets to attack. This build also provides healing and survivability so you can stay in the fight for longer.
For weapons, you can use any weapon you are comfortable with as they are primarily just for Fight For Your Life and during your skill's downtimes, which shouldn't be many. We do, however, recommend using Jakobs and Vladof guns, specifically Shotguns, Submachine Guns, and Assault Rifles so you can stay in close to mid-range.
Best Rafa (Exo-Solder) Build Playstyle
Multi-Purpose Build
Be it for levelling Rafa, or for farming bosses, this build can do them both. As long as you can attack enemies, be it a crowd of mobs or a singular boss, you will be able to stay in Arc-Knives mode indefinitely.
If you are facing difficulties in using this build for either of these purposes, consider checking out our dedicated Leveling Build and Boss Farm Build!
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