The Feedbacker is the blue arm variant, equipped by default. It is a blue-and-black mechanical arm with round plating. The forearm has a hydraulic tube and a blue sleeve, while the upper arm and bicep are primarily composed of exposed black machinery. Along the back of the arm runs a blood-filled cable.
The arm can punch to deal a quick jab with relatively low damage, or, with precise timing, parry certain enemy attacks as well as many of the player's own projectiles.
Mechanics
When attacking, the Feedbacker performs a short, quick punch which deals 1 damage to enemies with very little knockback.
The Feedbacker has the ability to pick up held objects (such as but not limited to 
Skull Keys, Books, and Torches). Skull Keys and Torches remain held until placed on a pedestal, and objects such as Books can be thrown at any time.
The Feedbacker's primary mechanic is the arm's ability to parry many enemy attacks and certain player projectiles with precise timing. Parries against enemy attacks are indicated by a bright screen flash and a hitstop, and have the ability to refill the player's stamina to maximum and health to full or their Hard Damage limit.
When an enemy fires a projectile such as a 
Hell Orb or 
Seeker Orb, the projectile can be parried once it is within punching distance of the player, causing it to redirect in the direction that the player was facing when parrying, and explode on contact with any surface or enemy. Any other projectiles, such as the 
Insurrectionist's boulder or the 
Swordsmachine's shotgun pellets, have effects when parried dependent on the projectile's specific behaviors. Enemy projectiles have three "mercy frames" between hitting the player and damage being dealt, to provide a slight amount of leniency.
The Feedbacker can also parry enemy melee attacks. Parrying melee attacks involves punching the enemy directly within the timing of or shortly before an attack, usually indicated by a bright yellow flash which appears on the enemy. Parrying an enemy's melee attack deals varying damage depending on the enemy, with some melee parries being guaranteed instant kills. Some melee parries cancel the enemy's attack, in an action known as an interruption, while others do not cancel the attack performed.
The Feedbacker's ability to punch certain player projectiles can be used with several different weapons. Punching player-based projectiles does not refill stamina and health. Player projectiles which can be punched include:
- The
Marksman Revolver's coins, which, when punched, redirect into the nearest enemy and bounce above them.
- The
Shotgun's pellets, which are boosted in speed and deal an explosion on contact with surfaces or enemies when parried.
- The
Sawed-On Shotgun's chainsaw, which can be punched when returning to the player on its tether to boost it forward again, or when detached to redirect its trajectory.
- The
Sawblade Launcher's Sawblades, which are redirected in the trajectory aimed towards when punched and have their damage increased.
- The
Screwdriver Railcannon's drill, which can be punched when embedded inside an enemy to punch it out and boost it in the direction punched, dealing its remaining damage and hit any enemies in its path.
- The
S.R.S. Cannon Rocket Launcher's cannonball, which can be punched to boost it quickly forward, piercing through any enemy it kills.
Some player projectiles induce both hitstop and a screen flash when punched, such as Shotgun pellets, Screwdriver drills, and S.R.S. Cannon cannonballs. Others induce hitstop but not a bright flash, such as Sawed-On Shotgun chainsaws and Sawblade Launcher sawblades. The Marksman Revolver's coins are the exception, as they induce neither.
A list of every parriable attack which can be performed by each enemy is found in the table below:
| All Parriable Attacks
|
| Enemy
|
Parried Actions
|
Parry Type
|
| HUSKS
|
 Filth
|
Lunging Bite
|
MELEE
|
 Stray
|
Hell Orb Casting
|
INTERRUPTION (Melee/Projectile)
|
| Hell Orb
|
PROJECTILE
|
 Schism
|
Hell Orb Casting
|
INTERRUPTION (Melee/Projectile)
|
| Hell Orb
|
PROJECTILE
|
 Soldier
|
Hell Orb Casting
|
INTERRUPTION (Melee/Projectile)
|
| Soldier Kick
|
MELEE
|
| Hell Orb Scatter
|
PROJECTILE
|
 The Corpse of King Minos
|
Fist Punch
|
MELEE
|
| Open-Palm Punch
|
| Fist Slam
|
| Seeker Orb
|
PROJECTILE
|
| Hell Orb
|
| Sisyphean Insurrectionist
|
Malicious Flail
|
INTERRUPTION (Melee/Projectile)
|
 Ferryman
|
Second Oar Attack
|
MELEE
|
| Second Kick
|
| Stinger
|
| Explosive Overhead
|
| Backstep
|
| MACHINES
|
 Drone
|
Hell Orb
|
PROJECTILE
|
| Kamikaze Dive
|
| Hell Orb Casting
|
INTERRUPTION (Melee/Projectile)
|
| Swordsmachine
|
Three Slashes Combo
|
MELEE
|
| Running Slash
|
| Roundabout Throw
|
| Straight Throw
|
INTERRUPTION (Melee/Projectile)
|
| Shotgun Pellets
|
PROJECTILE
|
 Mindflayer
|
Whip
|
MELEE
|
| Seeker Orbs
|
PROJECTILE
|
 Sentry
|
Scope Shot
|
INTERRUPTION (Melee/Coin)
|
 Gutterman
|
Shield Bash
|
MELEE
|
| Punch
|
 Guttertank
|
Whiffed Punch
|
MELEE
|
 V2 (Both Fights)
|
Revolver Shot
|
PROJECTILE
|
| Piercer Charge Shot
|
| Shotgun Pellets
|
 1000-THR "Earthmover"
|
Giant Seeker Orb (Brain)
|
PROJECTILE
|
| Seeker Orb (Security System)
|
| Hell Mortar (Security System)
|
| DEMONS
|
 Malicious Face
|
Hell Orb Volley
|
PROJECTILE
|
| Malicious Laser
|
INTERRUPTION (Melee/Projectile/Coin)
|
 Cerberus
|
Apple Throw
|
PROJECTILE
|
 Mannequin
|
Seeker Orb
|
PROJECTILE
|
| Slash
|
MELEE
|
 Hideous Mass
|
Hell Mortars
|
PROJECTILE
|
| Harpoon
|
MELEE
|
 Leviathan
|
Hell Orb Barrage
|
PROJECTILE
|
| Lunge
|
MELEE
|
 Minotaur
|
Bull Charge
|
MELEE
|
| ANGELS
|
 Virtue
|
Divine Light
|
INTERRUPTION (Melee)
|
| Death Orb
|
PROJECTILE
|
 Gabriel, Judge of Hell
|
Spear Throw
|
PROJECTILE
|
| Twin Axes
|
| Sword Toss
|
| Formation Swords (Higher Difficulties)
|
 Gabriel, Apostate of Hate
|
Swift Strikes Finisher
|
MELEE
|
| Frontwards Charge
|
| Heavy Hits
|
| Formation Swords
|
PROJECTILE
|
| Sword Toss
|
| ???
|
 Very Cancerous Rodent
|
Explosive Hell Orb
|
PROJECTILE
|
 Mysterious Druid Knight (& Owl)
|
Seeker Orb Barrage (Fuller Auto)
|
PROJECTILE
|
| Hell Orb Barrage (Full Auto)
|
| Kamikaze Dive
|
INTERRUPTION (Melee/Projectile)
|
 Flesh Prison
|
Seeker Orb Twirl
|
PROJECTILE
|
| Piercing Stare (Eye Minion)
|
INTERRUPTION (Melee/Coin)
|
| Malicious Beam (Mini-MalFace)
|
 Flesh Panopticon
|
Hell Mortars
|
PROJECTILE
|
| PRIME SOULS
|
 Minos Prime
|
Seeking Snake
|
PROJECTILE
|
| Dropkick ("Judgement")
|
MELEE
|
| Fist Slam ("Thy end is now")
|
 Sisyphus Prime
|
Self-Destruct ("This will hurt")
|
INTERRUPTION (Melee)
|
| Stardust Breaker ("DESTROY")
|
MELEE
|
| Sumo Combo Finisher ("You can't escape")
|
| Sumo Clap ("BEGONE")
|
The Feedbacker also has the ability to break 
Idols with its punch.
Usage
Although the base punch of the Feedbacker alone is small and relatively weak, the utility that its ability to parry offers is immeasurable. The majority of enemy attacks are parriable with the Feedbacker, meaning that the player can reliably counter most enemies with proper coordination and timing. When caught in situations where attempting to simply dodge or avoid an attack is too risky, or even impossible, a parry can defend oneself against dangerous threats such as high-damage homing projectiles like Seeker Orbs and Hell Mortars, or big explosions like the Malicious Face's beam attack. A melee parry often cancels the countered attack and prevents it from being performed, but in situations where it does not, dodging directly after the parry is recommended for safety.
A parry can also function fairly well as an offensive tool. Projectiles redirected using the Feedbacker can be punched into the enemy that shot them or even other enemies, allowing the player to take advantage of various enemy attacks. Offensive parries can even be performed after an enemy's death, such as a Drone's suicide dive. Melee parries, in most cases, deal significant damage to the enemy parried, and in some cases can even instantly kill the enemy, like when fighting Mannequins or Soldiers. Some parries, like a Hideous Mass harpoon parry or an Insurrectionist cannonball, offer a reward in the form of stunning the enemy and removing a large portion of health, but are also highly-risky due to their difficult timing.
Aside from being strong both offensively and defensively, parries serve the ability to assist in the player's self-preservation. Since parries instantly refill health, they allow the player to maintain an aggressive position against powerful enemies and even work as an alternate healing option against enemies sanded by 
Stalkers. The player must still maintain caution, however, as parries do not refill a player's health past the Hard Damage limit, meaning that if the player is overwhelmed and low on Style to get rid of Hard Damage they still have to play things safely. Parries also possess the ability to instantly refill a player's stamina, which gives the player the opportunity to use parries to counter an attack and then quickly dodge out of the way using a dash jump via their newly-refilled stamina. This is especially useful in cases where a parry does not cancel a countered melee attack.
Though the Feedbacker's ability to parry enemy attacks is its primary use case, parrying the player's own attacks is also an integral part of a well-rounded arsenal. Punching the Marksman's coins is a great combo-filler technique that can work in tandem with other coin shots or hitscan weapons like the 
Railcannon, and can be maintained for long coin-juggling chains with good coordination. Projectile Boosts performed with the Shotgun allow a reliable explosive option from almost any distance, and can be combined with shotgun swapping techniques to minimize weapon cooldowns. The Sawed-On Shotgun benefits extremely greatly from Feedbacker punches, since they allow it to be maintained theoretically infinitely and stack multiple chainsaws together at once; however, due to how a tethered chainsaw stagnates when coming into contact with enemies, it can be difficult to time a punch correctly. Redirecting Sawblade Launcher sawblades with a punch is a good way to ramp up high damage quickly against stationary or slow-moving enemies, and lends itself well to the usage of a magnet-based sawblade trap. Punching the Screwdriver Railcannon's drill deals incredible amounts of damage near-instantaneously, and allows the player to redirect the drill into another enemy and punch it back and forth between multiple enemies as many times as it can be maintained. The S.R.S. Cannon's cannonball, when punched, can clear through crowds of low-health enemies and even kill some larger enemies like Cerberi, Virtues and Sentries instantly.
The Knuckleblaster is the red arm variant, obtained in 1-4: CLAIR DE LUNE. It is a red-and-grey bulky mechanical arm, with two large exhaust pipes on the elbow, an exposed piston on the forearm, and three large, flat fingers possessing bolts on each knuckle.
It can punch to deal a heavy blow with strong knockback, and can be held down to blast the shells inside, releasing a close-range shockwave.
Mechanics
The Knuckleblaster arm, on attack, releases a strong, heavy punch which deals 2.5 damage on direct hit. Punches from the Knuckleblaster are slower than the Feedbacker with a very short delay between the input and the actual hit, and add greater value to Punch Exhaustion's cooldown between both fists.
The Knuckleblaster has very high knockback, and can punch Light- or Medium-weight enemies far distances. If the Knuckleblaster is used to punch an enemy that can take fall damage directly downwards, it splatters the enemy on contact with ground. If the Knuckleblaster kills a small enemy on hit, such as a Soldier, it causes the enemy to burst into a large shower of blood.
The Knuckleblaster has the ability to pick up held objects (such as but not limited to Skull Keys, Books, and Torches). Skull Keys and Torches remain held until placed on a pedestal, and objects such as Books can be thrown at any time.
The Knuckleblaster's primary unique mechanic is performed by holding down the punch key when attacking with the arm. When held down, the Knuckleblaster produces a close-range shockwave shortly after punching, indicated by the arm ejecting the shells inside. The shockwave is harmless to the player, dealing 1 damage to enemies caught inside and launching any Light- or Medium-weight enemies a short distance in the air. After performing a shockwave, the Knuckleblaster's energy is briefly expended, playing a reloading animation that ejects spent shells from its knuckles and makes it unable to punch again for a slightly longer period of time.
When firing the Sawed-On Shotgun's chainsaw on a tether, punching it with the Knuckleblaster causes it to break and detach from its tether, ricocheting against surfaces.
The Knuckleblaster can break the Gutterman's shield via a direct hit or shockwave blast, and additionally has the ability to break Idols with either its punch or shockwave.
The Knuckleblaster can also punch dying Mindflayers, redirecting them in the direction of the punch and causing them to explode on contact with surfaces/enemies. The Knuckleblaster can, as well as this, interrupt Sentries charging a shot with a direct punch.
Usage
The Knuckleblaster is a simple weapon mechanically, but one which can be employed in almost any circumstance for strong damage and support. Its heavy punch can be used almost anywhere, at any time, in combination with other weapons like the Shotgun at close range. Though it is slower than the Feedbacker, and has greater Punch Exhaustion, occasional Knuckleblaster punches during a combo with another weapon that doesn't involve punching can be incredibly beneficial for extra damage, even reaching important damage thresholds (like instantly killing a Sentry with a high-velocity 
Impact Hammer hit and a simultaneous Knuckleblaster punch).
The Knuckleblaster's healing capabilities are significant, most so against small, low-health enemies. A normal punch heals 30 or so health, but critical punches on enemy weakpoint heal even more, and a punch which kills a small enemy like a Soldier causes the enemy to explode into a shower of blood, instantly regenerating all lost health and serving as an efficient means of dispatching such threats without potentially using up other weapons.
The high knockback of a Knuckleblaster punch makes it a viable and stylish method of pushing enemies off ledges or into the ground. Splattering enemies into the ground via the Knuckleblaster is an effective method of dealing with threats susceptible to fall damage. In general gameplay the only enemies to which this technique realistically applies are the Schism and 
Streetcleaner, but in 
The Cyber Grind this method becomes invariably more important as many small enemies start to become radiant, giving them greater amounts of health which can be bypassed with fall damage.
The shockwave of the Knuckleblaster is a good utility for taking out very low-health enemies (such as Filth), and dealing chip damage to larger ones. Enemies launched into the air by a shockwave can be dealt with using airshot-based attacks such as those of the 
Rocket Launcher. The shockwave also reflects enemy projectiles like Hell Orbs and Seeker Orbs, which means it is an alternative to parrying that works at greater range and can deal with several projectiles at once. Redirecting multiple projectiles at the right angle to hit an enemy deals incredible amounts of damage very quickly, and allows the player to take out bigger enemies like Malicious Faces with precise timing.
The Knuckleblaster's capability of breaking Gutterman shields makes it, in most cases, the first weapon to use against them, shutting down their damage resistance as quickly as possible with ease. This may not always be advisable, though, due to their faster lock-on time when unshielded. Since the shockwave can also break the shield, a Knuckleblaster punch is a reliable option even in chaotic situations where it is impossible to land a direct hit on the Gutterman. The shockwave also makes the Knuckleblaster the most reliable method of dispatching Idols, ensuring that the player can still quickly kill one in dangerous circumstances even if they miss the initial punch.
The Whiplash is the green arm variant, obtained in 4-4: CLAIR DE SOLEIL. It is a green-and-grey multi-jointed arm with rounded plating on the elbow and forearm, and a spear attached to the palm which is wrapped around the arm via a cable.
It can be fired to release a grappling hook which can latch onto enemies and either pull them towards the player or pull the player towards them, depending on their weight.
Mechanics
On fire, the Whiplash releases a spear on a winch which flies directly outward in a distance from the player. The attack can be held down to extend the spear outward further, and begins to reel back once it reaches its maximum possible range, hits a surface, or is released. If the Whiplash intersects with a possible target for the spear to attach to, it stops and sticks to the target until the arm is released.
The Whiplash can target enemies and 
Hookpoints with its spear, latching onto them and pulling on release. When latching onto enemies, the Whiplash deals 0.2 damage and pulls back. Light-weight enemies such as Strays and Schisms are pulled towards the player on release, while Medium- and Heavy-weight enemies such as Mannequins, Malicious Faces and Sentries pull the player towards them.
When latching onto Hookpoints, the player receives unique effects depending on the type of Hookpoint. Green Hookpoints pull the player towards them, releasing upon contact with the Hookpoint. Blue Hookpoints pull the player towards them, launching them past the Hookpoint in whatever direction they were pulled towards. Yellow Hookpoints do not pull the player towards them, but very briefly suspend the player in midair, deactivate the Hookpoint, and activate an object or trigger that is connected to it. After a short time, the Hookpoint reactivates and whatever object/trigger that was activated by it deactivates.
While mid-reel towards a Medium/Heavy-weight enemy or a Hookpoint, the player has the ability to dash and slam while reeling, and can cancel the Whiplash's reel at any time by jumping, punching with the Feedbacker or Knuckleblaster, or pressing the Whiplash key a second time. Punching or using the Whiplash to cancel preserves the momentum of the player, while jumping does not.
The Whiplash has the ability to retrieve held objects (such as but not limited to Skull Keys, Books, and Torches) by latching onto them with its spear. However, unlike the Feedbacker and Knuckleblaster, the Whiplash does not hold said objects and they can only be held if either of the other arms are equipped.
On difficulties Standard and above, when reeling in towards enemies, the Whiplash gradually replaces any empty health in the player's health bar with Hard Damage at a rate of 60/sec, temporarily reducing the player's maximum health. The amount of Hard Damage which can be gained via Whiplash is up to 50. Hard Damage produced by the Whiplash gradually depletes after a short time, depleting faster if the player has a higher style rank, and not appearing whatsoever if the player is at the highest possible style rank (ULTRAKILL style rank). When used underwater, the Whiplash does not add Hard Damage.
The Whiplash can reel certain projectiles, including player- or enemy-fired rockets and coins. When a rocket comes into contact with the spear of the Whiplash, it is carried along the path of the spear as it travels, exploding harmlessly on contact with surfaces and creating a damaging explosion on contact with enemies or the player, unless both the player and the rocket are falling/flying downwards, in which case the player begins to ride the rocket. When the Whiplash's spear touches a coin, it bounces the coin in the air, allowing it to stay perpetually suspended.
Usage
Unlike other weapons, which focus primarily on damage and defensive capabilities, the Whiplash is first and foremost a movement/support tool, which works to the player's benefit by quickly getting them across distances, between enemies, and away from dangerous situations. Against enemies, the Whiplash helps to close the gap between the player and their target, bringing Light-weight enemies into the air where they can be taken out quickly with a Knuckleblaster punch or an airshot with the Rocket Launcher. Medium- and Heavy-weight enemies can be latched onto as a means to traverse long distances in big arenas and get close to use weapons most effective at point blank, like the Shotgun. However, the player must be cautious of attacks from the enemy they are flying towards and dash out of the way or stop the whiplash if necessary. Additionally, some enemies possess armored body parts, such as the Gutterman's shield or Hideous Mass's stone shell, which cannot be hooked onto and require the player to find another angle or close the gap via different means.
Whenever the player is on low health, they must take care when using the Whiplash, as the quick Hard Damage buildup which results from excessive use of the weapon catches the player in dangerous situations with no ability to heal. The Whiplash can still be used as a way to reel into the healing range of enemies on low-health, but cancelling the reel early with a Feedbacker/Knuckleblaster punch or another Whiplash input is recommended to minimize the amount of Hard Damage built up as the player approaches. This effect can alternatively be negated entirely by staying on high style ranks, but style is difficult to maintain for long periods of time, so this is not a method that should always be relied upon.
The Whiplash comes into play as a platforming tool in many sequences involving Hookpoints, especially in later levels. Hookpoints are often used in arenas with other enemies, serving as a method to get across the arena safely or get to enemies in hard-to-reach, higher locations. Unlike enemies, Hookpoints do not deal Hard Damage to the player, so a player can use them to approach targets far away for a heal or escape without risking themselves even further. Yellow Hookpoints activate certain sequences or gates that may allow the player to reach otherwise-inaccessible enemies or trigger objects to kill them.
Since the Whiplash is capable of attaching to rockets, it can be used as an explosive boosting tool at the cost of self-damage, by pulling a fired rocket towards the player. When falling, a rocket shot downward and hooked onto is mounted by the player and ridden, meaning that the Whiplash can be used to quickly rocket ride without necessitating use of the 
Freezeframe Rocket Launcher. Rockets can also be pushed into enemies during the time where the Whiplash's spear is extending outward, serving as a means to more quickly direct the projectile and perform more reliable airshots. Said rockets can also be frozen with the Freezeframe for a larger, more deadly explosion. The Whiplash's additional ability to juggle coins in the air is useful for prolonging their lifespan during longer combos, weapon cooldowns, or other wait-times.
Parries
Hell Orb or 
Seeker Orb, the projectile can be parried once it is within punching distance of the player, causing it to redirect in the direction that the player was facing when parrying, and explode on contact with any surface or enemy. Any other projectiles, such as the 
