The Zero Knuckle (ゼロナックル Zero Nakkuru) is a weapon Zero uses in Mega Man Zero 4, replacing both the Shield Boomerang and the rod weapons used in previous games. The Zero Knuckle consists of a Z-shaped chip implanted into Zero's palms. By punching enemies with the chip, Zero can rip off enemy parts and use them. A successful theft of such a part normally results in the destruction of most enemies, but some enemies like Yadokroid and Lamplort X will survive this attack at least once. The weapons or parts can have a number of uses, and some have limited ammunition. If a stolen weapon is out of ammo or simply of no use any longer, it can be thrown away by pressing Select or in the pause menu, which can hurt an enemy as well. Since Elemental Chips have been omitted from the game, it's unknown if the Zero Knuckle can use the chips like Zero's other weapons. It can also be charged, however the charged version of the Zero Knuckle is only a stronger punch. It is unknown whether this weapon was created by Cerveau or had been part of Zero all along, but artworks of Omega from Mega Man ZX show him having a Knuckle on his own, but with an Omega symbol (Ω) instead of a Z; this is most likely used for the Rekkoha and Rakuhouha.

The Weapon Plus Head Chip increases maximum ammo by 1.

Unlike the K Knuckle from Mega Man X8, the Zero Knuckle cannot make use of the EX Skills learned in the game. Also, the weapons it steals cannot be carried over to other areas.

List of Zero Knuckle weapons

Zero can hold only one of these weapons at a time.

Graphic Name Power Element Ammo Type Enemy Description
2-Way Shot
2 None Buster Gyro Cannon H Fires 2 shots diagonally.
3-Way Bomb
9/2 None x1 Bomb NicosCrabB Bomb that shoots 3 bullets on impact.
Balloon Bomb
8/4 None x1 Bomb NeedBalloon Explodes after being thrown a certain distance, firing 8 needles in all directions.
Beam Shot
6 None Buster BeamWalker Fires a laser, it is more powerful than the buster shot, and pierces through enemies.
Bee Rod
4 None Rod Appnet Zero attacks with an Appnet's stinger.
Bend Laser
6 None x8 Buster E-Laser Laser that bends itself when it coincides vertically with an enemy, changing its direction either upwards or downwards.
Blade Shield
1 None Shield SandDozer Reflects bullets.
Blaze Shot
4/7 Fire x8 Buster Variant Fire Fires a bomb forward, creating a flame that lingers for a moment. Can melt snow and burn some trucks in the opening stage.
Bound Tire
16 None x1 Bomb Kerberos Bounces off terrain, explodes after a few bounces. If it misses, Zero can pick it up again with the Z-knuckle.
Burst Bomb
4/6 x 4 None x3 Bomb Boxes in first stage. Powerful bomb that explodes with a wider range than most other bombs.
Cannon Buster
8 None x6 Buster RBCannon Lobs a green shot forward that bounces off terrain.
Card Key
4 None x1 Rod NicosCrabC Mainly used to open a door that leads to a Sub Tank. Immediately destroyed when used to attack an enemy.
Cross Shot
4/2 None Buster Crossbyne Fires a spiked ball. Depending on when it hits something, spreads needles either all diagonal directions, or fires vertically and horizontally.
Death Pierce
20 None x1 Saber One of Dr. Weil's 1st form attacks. Swings a powerful sword. Gets used up when an enemy is destroyed.
Drill Rod
3x9 None x6 Rod GangaGun Fires an extending drill. On enemy impact, it stops its extension, keeps drilling for a second and summons blobs of lava for extra damage. Can destroy certain blocks in the teleporter base.
Drill Shot
5x4 None x8 Buster Molegule Fires a single drill with moderate damage output, so it might pierce through weaker enemies.
Egg Bomb
12x12 None x1 Bomb Fire Renant's Egg Bombs Powerful bomb that explodes with a wider range than most other bombs. Very similar to the Burst Bomb, but has only one shot.
Electric Arm
6 Thunder Rod Pantheon Corpse A stab with an electric club. Short ranged, but fast and can be aimed in 8 directions.
Electric Rod
10/4 Thunder x6 Rod Raiken When the rod hits terrain, it sends sparks moving across the ground.
Electric Nail
5/5 Thunder Rod EleDeserter Creates an electric orb that lingers for a few moments. Good for "nailing" enemies in place.
Flame Sword
10 Fire Saber Faital An incredibly strong sword. Can replace the Z-Saber due to its power, but cannot perform combos.
Gear Bomb
14 None x1 Bomb Serpent Gear Normal bomb that travels straight horizontally.
Gyro Boomerang
10 None x1 Bomb Gyrator It acts like the thrown Shield Boomerang. It will get destroyed upon collision with a strong enemy. If it misses, Zero can pick it up again with the Z-knuckle upon return.
Heat Sabre
12 Fire Rod Variant Fencer Zero thrusts forward similar to a charged Recoil Rod. Deals Fire damage.  
Hive Bomb
2 None x1 Bomb Beeneran Fires a bomb that summons 3 bees. If touched, the bees will hurt Zero.
Ice Buster
6 Ice x8 Buster Glacial Lobs a chunk of ice to freeze enemies.
Ice Shield
1 Ice Shield Hechrysta
IM Shot
2 None Buster Yadokroid Fires shots that are automatically aimed at nearby enemies. Better tracking than the Search Shot, but slower projectile speed.
Iron Pipe
12 None x6 Saber Iron Pipe found in Hibernation Chamber.
Joint Bomb
8/8 None x4 Bomb Bonsect Normal bomb.
- - Buster Lamps in Hibernation Chamber. Repels scrap elves in the Hibernation Chamber.
Lamp Shield
- - Shield Lamplort X Blocks energy shots.
Lamp Burner
3x16 Fire x6 Buster Lamplort X Flamethrower. Can burn some obstacles in the opening stage.
Long Snapper
2x5 None Rod Poplan A Poplan head is thrust from Zero's arm, dealing constant damage as it snaps its jaws. Can pass through terrain and shields.
MagPunch N
MagnePunch N)
4 None Rod MagnePaN A punch that repels MagnePaN and MagneMineN, and disables MagnePaS and MagneMineS.
MagPunch S
MagnePunch S)
4 None Rod MagnePaS A punch that repels MagnePaS and MagneMineS, and disables MagnePaN and MagneMineN.
Mega Axe
16 None Saber Axeloid Acts like a non-elemental Flame Sword. It tends to be pretty convenient because of its power.
Mega Hammer
10 None Saber Moloid The same as the Mega Axe, but slower. Used to activate water pumps in Area Zero.
Met Shield
- - Shield Mettaur Blocks energy shots, but so small it offers little cover.
Mini Craban B
12 None x1 Bomb Mini Craban B Normal bomb.
Mini Craban R
12 None x1 Bomb Mini Craban R Normal bomb.
Neon Bomb
5x3 Thunder x2 Bomb CryoNeon Throws a bomb that leaves behind a large electric spark that lingers for a while.
Reflect Laser
4 None Buster RefleBeemer Fires two shots that reflect off of terrain. Slow rate of fire and low damage.
Rising Bomb
8/8 Fire x2 Bomb Bombadeer Throws a bomb, which upon impact with the ground, creates a single rising flame that lingers for a few moments.
Search Shot
2 None Buster ArcCannon Fires regular pellet shots, but will automatically aim towards enemies.
Sharp Shield
1 None Shield Yadokroid Similar to the Met Shield, but with a wider shield area. It also deals a little damage to enemies the moment Zero deploys it.
Spread Shot
2x4 None Buster Cannon Hopper Fires a volley of five energy shots in a spread pattern.
Steel Claw
10 None Rod Variant Claw Summons a giant metal claw.
Tang Rod
Tongue Rod)
4x2 None Rod Kerosh Acts like the Chain Rod, except that it's slower and penetrates enemies.
Tri Shot
4 None Buster Triaformer Automatically aims at targets similarly to the IM Shot, but the shots linger for a moment after being fired.
Vertical Shot
4 None Buster MeduHopper Does considerably more damage than normal shots, but is nearly useless because it can only fire up and down.
Water Gun
1 None x8 Buster Water pumps in the Area Zero mid-stage. Fires water for a short distance, weak against enemies but extinguishes fires.
Wave Bomb
8/8x8 Fire x1 Bomb Bongal Throws a bomb, which upon impact with the ground, creates a line of flames which linger for a few moments.
Wide Buster
5/4 None x4 Buster Variant Missile Fires a large missile, which blows up after traveling a very short distance, but summons 5 smaller missiles with unlimited range.