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User:Apollyon man/Sandbox/Mom's Knife

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Font TeamMeat M.pngFont TeamMeat o.pngFont TeamMeat m.pngFont TeamMeat '.pngFont TeamMeat s.png   Font TeamMeat K.pngFont TeamMeat n.pngFont TeamMeat i.pngFont TeamMeat f.pngFont TeamMeat e.png
Item icon
Item altar
 
 
Table dividing line 1.png
 
 
Tear appearance
Table dividing line 2.png
 
Devil Room Devil Room
Treasure Room Treasure Room
Greed mode only Devil Room Devil Room
Greed mode only Treasure Room Treasure Room
Table dividing line 3.png
 
Added in Afterbirth(page 1, column 11, row 6)
Removed in Afterbirth(page 2, column 1, row 2)
 
Mom's Knife Defeat Satan as IsaacMom's KnifeMom's Knife

Mom's Knife is a Special unlockable passive item.

Effects[edit | edit source]

  • Isaac's tears are replaced by a knife that pierces enemies and can travel through obstacles. Holding down the fire button increases its range and power.
    • The knife can hurt enemies while Isaac is holding it.
    • The knife deals 2x Isaac's damage while held and 6x damage at the furthest possible point of its arc, regardless of the actual maximum range stat.

Notes[edit | edit source]

  • The knife can be held and fired diagonally. Firing the knife diagonally requires a frame perfect input. However, this can be done easily with a controller's analog stick.
  • The knife will not work in challenges with the Blindfolded effect.

Synergies[edit | edit source]

  • Added in Afterbirth †Bookworm Transformation: 2 knives occasionally (based on luck) will fire forward in the direction aimed, splitting apart in trajectory slightly.
  • Brimstone BrimstoneBrimstone Rebirth Icon.pngTears are replaced by a laser beam that pierces through all enemies and obstacles in its path and deals high damage. Can only be fired after a short charge-up period.: Firing the knife also shoots a barrage of knives that goes across the screen, with each knife doing 80% of Isaac's damage. The longer the charge, the more knives are added. This effect does not work with Azazel's default mini brimstone. The brimstone-knives do not benefit from A Lump of Coal A Lump of CoalA Lump of Coal Icon.pngThe more distance tears travel, the more damage they will do..
  • Chocolate Milk Chocolate MilkChocolate Milk Icon.pngGrants charged tears that deal greater damage when fully charged.: Tears up instead of additional damage or charge effects. Knife will also be colored brown.
  • Added in AfterbirthContinuum ContinuumContinuum Afterbirth Icon.png+2.25 Range Up. +1.5 Tear Height. Isaac's tears travel through walls and appear out of the opposite wall. Isaac's tears also travel over rocks and objects.: The knife can now travel through walls and appear out of the opposite wall but will still have the boomerang effect.
  • Epic Fetus Epic FetusEpic Fetus Icon.pngIsaac's tears are replaced with guided missiles, like those used by the Doctor's Remote.: No effect.
    • Added in Afterbirth Each explosion shoots 10 knives in a circle from the point of impact.
  • Eve's Mascara Eve's MascaraEve's Mascara Icon.pngDoubles damage, halves tears stat, and greatly reduces shot speed.: Damage is doubled. However, the knife takes longer to charge.
  • Fire Mind Fire MindFire Mind Icon.pngGrants flaming tears that deal burning damage over time. Tears have a chance to explode on impact with an enemy, which creates a fire at the location of the explosion.: Still applies burning but no longer explodes.
  • Added in Afterbirth †Flat Stone Flat StoneFlat Stone Icon.pngTears bounce off the floor. Tears that hit an enemy after bouncing deal splash damage to all nearby enemies for 25% of Isaac's tear damage.: Knife bounces as it flies away from Isaac, each bounce splash causing Isaac's base damage.
  • Added in Afterbirth † The Forgotten: The knife attaches to the Forgotten's bone club, forming a scythe with a larger swing and higher damage.
  • Added in Afterbirth †Ghost Pepper Ghost PepperGhost Pepper Icon.pngAdds a chance to shoot a fire that damages enemies and remains in place until it deals enough damage or the room is left.: The flames can shoot from Isaac while holding the fire button.
  • Gnawed Leaf Gnawed LeafGnawed Leaf Icon.pngAfter standing still and not shooting for a short time, Isaac turns invincible until he moves or shoots.: The held knife can damage enemies while Isaac is invincible.
  • Godhead GodheadGodhead Icon.pngIncreases damage and range while reducing tears and shot speed. Grants homing tears and tears gain a damaging halo.: The knife homes in on enemies, but it does not gain a damaging halo.
  • Guppy Transformation: Knife hits will rarely spawn an attack fly.
  • Added in Afterbirth †Haemolacria HaemolacriaHaemolacria Icon.pngTears are now fired in an arc. Upon hitting the floor, an obstacle, or an enemy, they burst into many smaller tears in all directions. Increases tear delay.: Haemolacria works with minimal tear delay while Mom's Knife has to be charged.
  • Homing Tears: Knives home in on enemies and colors the knife purple. It will stick on enemies for a second and make small lunges towards other enemies.
  • The Inner Eye The Inner EyeThe Inner Eye Icon.pngGrants triple shot but decreases tears.: Isaac holds only one, but shoots three knives. Slower charge time.
  • Ipecac IpecacIpecac Icon.pngReplaces tears with explosive and poisoning projectiles fired in an arc from the mouth.: Knife turns green and may poison monsters that hit it.
    • Added in Afterbirth † Also adds +4 damage.
  • Loki's Horns Loki's HornsLoki's Horns Icon.pngGives a random chance for projectiles to fire in all 4 cardinal directions.: Adds three knives in the other directions that the primary knife is facing. These knives will sometimes fire when the primary knife is fired. This is affected by luck; the higher Isaac's luck is, the higher the chance the other knives will fire as well. Like the primary knife, they can be used as melee weapons.
  • Lost Contact Lost ContactLost Contact Icon.pngEvery tear has a small shield which will allow it to block one enemy projectile.: The knife will block bullets, even when held. Furthermore, the knife will not vanish after canceling a bullet, and therefore can cancel out several bullets at once while being shot or held.
  • The Ludovico Technique The Ludovico TechniqueThe Ludovico Technique Icon.pngInstead of firing tears, Isaac controls one floating tear that hover over obstacles. This tear deals constant damage when held in place over an enemy.: Isaac controls a floating knife that deals 2x Isaac's damage. Tears stat is ignored and damage is dealt at a rate equivalent of 5 tear delay.
    • The Ludovico Technique + Mom's Eye Mom's EyeMom's Eye Rebirth Icon.pngAllows Isaac to fire tears from the back of his head.: Isaac controls a floating knife surrounded by 1 rotating knife.
    • The Ludovico Technique + The Inner Eye The Inner EyeThe Inner Eye Icon.pngGrants triple shot but decreases tears.: Isaac controls a floating knife surrounded by 2 rotating knives.
    • The Ludovico Technique + Mutant Spider Mutant SpiderMutant Spider Icon.pngGrants quadruple shot but decreases tears.: Isaac controls a floating knife surrounded by 3 rotating knives.
    • The Ludovico Technique + Lost Contact Lost ContactLost Contact Icon.pngEvery tear has a small shield which will allow it to block one enemy projectile.: Floating knife loses almost all ability to block bullets. Only blocks shots that cross a very specific, small point on the knife. (Seems to be close to where hilt meets blade on the sprite.)
    • The Ludovico Technique + Loki's Horns Loki's HornsLoki's Horns Icon.pngGives a random chance for projectiles to fire in all 4 cardinal directions.: Loses Loki's Horns effect; Isaac controls only one floating knife.
  • Mom's Eye Mom's EyeMom's Eye Rebirth Icon.pngAllows Isaac to fire tears from the back of his head.: Adds a second knife in the opposite direction that the primary knife is facing. This knife can sometimes fire when the primary knife is fired. This is affected by luck; the higher Isaac's luck is, the higher the chance the other knife will fire as well. Like the primary knife, it can be used as a melee weapon.
    • Mom's Eye + Loki's Horns Loki's HornsLoki's Horns Icon.pngGives a random chance for projectiles to fire in all 4 cardinal directions.: Results in a total of four knives like Loki's Horns on its own, but the secondary knives fire with the same frequency that the single Mom's Eye knife would.
  • Added in Afterbirth Mom's Knife Mom's KnifeMom's Knife Rebirth Icon.pngIsaac's tears are replaced by a knife that pierces enemies, can travel through obstacles, and can hurt enemies while Isaac is holding it. Holding down the fire button before firing increases its range and power.: If picked up twice in the same run, two knives are fired at once.
  • Added in Afterbirth Monstro's Lung Monstro's LungMonstro's Lung Icon.pngIncreases damage and grants a charged shot that fires multiple tears in the same fashion as Monstro.: Fires a cluster of 3-5 knives at maximum charge, each dealing 2x damage.
  • Mutant Spider Mutant SpiderMutant Spider Icon.pngGrants quadruple shot but decreases tears.: Isaac holds only one, but shoots four knives. Slower charge time.
    • Mutant Spider + The Inner Eye The Inner EyeThe Inner Eye Icon.pngGrants triple shot but decreases tears.: Isaac shoots seven knives.
  • My Reflection My ReflectionMy Reflection Icon.pngGives Isaac's tears a boomerang effect, and increases range and shot speed.: No effect.
  • Poison Tears: Knives gain a chance to poison enemies.
  • Proptosis ProptosisProptosis Rebirth Icon.pngTears start out massive with high damage, and then shrink down and become weaker over a short range.: The Knife deals double damage regardless of range.
  • Strange Attractor Strange AttractorStrange Attractor Rebirth Icon.pngPickups, trinkets, and monsters are magnetically attracted to Isaac's tears.: Enemies and pickups are attracted to the knife, even when not charging or firing.
  • Tammy's Head Tammy's HeadTammy's Head Icon.png1 roomsShoots 10 tears in a circle around Isaac, which retain the damage, shot speed, and special effects (such as poison) of Isaac's tears.: Fires 10 knives in a circle around Isaac, dealing massive damage.
  • Tech.5 Tech.5Tech.5 Rebirth Icon.pngGrants a unlimited range piercing laser with random rate of fire that does not replace tears. The laser might occasionally fire with the effect of a random item or trinket, such as Hook Worm, Spoon Bender or Tiny Planet.: Both fire normally.
  • Added in AfterbirthTech X Tech XTech X Icon.pngTears are replaced with laser rings that pierce through enemies and deal damage to enemies within them. Can be charged to increase the size of the ring.: Both fire normally.
  • Technology 2 Technology 2Technology 2 Icon.pngDecreases damage and replaces right eye tears with a unlimited range, piercing laser which fires continuously.: While charging Mom's Knife, Technology 2 will still fire.
  • Trinity Shield Trinity ShieldTrinity Shield Icon.pngIsaac gains a shield that protects him from enemy shots.: Blocks bullets in the direction the knife is held, giving enough protection to walk up to and melee enemies, or just to safely shoot the knife.
  • Unicorn Stump Unicorn StumpUnicorn Stump Icon.png1 roomsUpon use, grants invulnerability and increased speed for five seconds, but removes the ability to shoot tears. and other invincibility items: Even though the knife cannot be fired, the knife will deal damage while Isaac is invincible.
  • Added in AfterbirthThe Wiz The WizThe Wiz Icon.pngTears simultaneously fire out of both eyes diagonally, similar to the effect of the R U A Wizard? pill. Isaac's tears also travel above all obstacles.: Grants two knives that fire diagonally.

Interactions[edit | edit source]

  • Anti-Gravity Anti-GravityAnti-Gravity Icon.png-2 Tear Delay. Tears float in position until firing ceases, after which they will fly off in the direction they were shot in.: Only tear delay down applies.
  • Added in Afterbirth †Compound Fracture Compound FractureCompound Fracture Icon.pngIncreases range. Tears turn into bones, which shatter into 1-3 bone shards upon hitting an enemy or obstacle.: Overridden by Mom's Knife.
  • Cricket's Body Cricket's BodyCricket's Body Icon.pngGrants -1 Tear Delay and reduces Range. When tears hit an object or deplete their range, they spawn 4 smaller tears, whose Range and Damage scale with Isaac's.: Tear delay and range down. No splitting effect.
  • Cursed Eye Cursed EyeCursed Eye Icon.pngGrants charged tears that can be fired in a tight burst of four. Getting hit while charging will teleport Isaac into another room.: Overridden by Mom's Knife.
  • Dead Onion Dead OnionDead Onion Icon.pngGrants piercing and spectral tears. Increases tear size (without increasing damage) while greatly reducing range and shot speed.: No effect.
  • Death's Touch Death's TouchDeath's Touch Icon.pngIncreases Damage by 1.5, reduces Tears by 0.3 and increases tear size. Grants piercing tears. Tears are replaced by Death's scythes, which is a cosmetic effect only.: Increased damage and decreased tear rate. No scythe visual effect.
  • Dr. Fetus Dr. FetusDr. Fetus Icon.pngTears are replaced by bombs that benefit from bomb-enhancing effects and slide for a fixed time after being fired.: Overridden by Mom's Knife.
    • Added in Afterbirth Both the knife and the bombs fire normally.
  • Added in AfterbirthExplosivo ExplosivoExplosivo Icon.pngIsaac's tears have a chance to stick to enemies and explode.: Overridden by Mom's Knife.
  • Added in Afterbirth †Euthanasia EuthanasiaEuthanasia Icon.pngAdds a chance to fire needles. If a needle kills an enemy, it bursts into more needles.: Overridden by Mom's Knife.
  • Added in Afterbirth †Eye of Belial Eye of BelialEye of Belial Icon.pngGrants piercing tears. After piercing one enemy, tears start homing and deal double damage.: Overridden by Mom's Knife.
  • Added in AfterbirthHoly Light Holy LightHoly Light Icon.pngIsaac has a random chance to fire a Holy tear, which, when it hits an enemy, will spawn a Crack the Sky-style light beam on the same enemy, dealing damage.: No effect.
  • Added in Afterbirth †Lachryphagy LachryphagyLachryphagy Icon.pngIsaac's tears decelerate as they travel. Upon stopping or hitting an obstacle, they burst into 8 tears in all directions. Tears can be fired into other tears to feed them, increasing their damage.: Overridden by Mom's Knife.
  • A Lump of Coal A Lump of CoalA Lump of Coal Icon.pngThe more distance tears travel, the more damage they will do.: Gives no damage boost but colors the knife dark brown.
  • Added in AfterbirthMarked MarkedMarked Icon.pngIsaac will now fire tears automatically directed at a red target on the ground which is controlled by the player. This allows for a full 360 degree tear firing radius. Can be overridden by other tear modifiers such as Mom's Knife or Brimstone.: Only tears up and range up apply.
  • Monstro's Lung Monstro's LungMonstro's Lung Icon.pngIncreases damage and grants a charged shot that fires multiple tears in the same fashion as Monstro.: Overridden by Mom's Knife.
    • Added in Afterbirth Firing a knife causes several other knives to shoot out at random directions.
  • Mysterious Liquid Mysterious LiquidMysterious Liquid Icon.pngTears leave a small, short lasting pool of creep on impact or when their range is depleted.: Overridden by Mom's Knife.
  • Number One Number OneNumber One Icon.png+1.5 tears, -17.62 range: Greatly reduces Mom's Knife range.
  • The Parasite The ParasiteThe Parasite Icon.pngIsaac's tears split in two when they hit something.: Overridden by Mom's Knife.
  • Piercing Tears: No effect.
  • Added in Afterbirth †Pop! Pop!Pop! Icon.pngReplaces Isaac's tears with eyeballs that can bounce off of each other. The eyeballs are not limited by range, and will instead dissipate when they stop moving or when hitting an enemy or obstacle.: Overridden by Mom's Knife.
  • Proptosis ProptosisProptosis Rebirth Icon.pngTears start out massive with high damage, and then shrink down and become weaker over a short range.: Damage is doubled and no damage decrease with distance.
  • Added in AfterbirthPupula Duplex Pupula DuplexPupula Duplex Icon.pngTransforms Isaac's tears into a wide arc shape which gives them a much larger hitbox. Gives Isaac spectral tears which allows them to travel through objects in the environment (i.e. rocks).: Overridden by Mom's Knife.
  • Rubber Cement Rubber CementRubber Cement Icon.pngTears bounce off walls, enemies, and environmental objects.: Overridden by Mom's Knife.
  • Scorpio ScorpioScorpio Icon.pngGrants poison tears, which deal damage over time when inflicted.: Overridden by Mom's Knife.
  • Soy Milk Soy MilkSoy Milk Icon.pngTears shrink and do much less damage, but fire in very rapid succession.: Damage drastically reduced at the benefit of a slightly better fire rate.
  • Technology TechnologyTechnology Icon.pngReplaces tears with a piercing laser with unlimited range.: Overridden by Mom's Knife.
    • Added in Afterbirth Both the knife and the laser fire normally.
  • Tiny Planet Tiny PlanetTiny Planet Icon.pngRange up and makes shot tears revolve around Isaac until they drop.: Knives go in a spiral around Isaac; the longer the knife is charged, the bigger the spiral. Not recommended, as this makes Mom's Knife almost impossible to aim.
  • Added in AfterbirthTractor Beam Tractor BeamTractor Beam Icon.pngIsaac emits a beam from his face. Isaac's tears travel in the path of the beam.: When Isaac changes direction, the knife snaps into the direction Isaac is facing.
  • Added in Afterbirth †Trisagion TrisagionTrisagion Icon.pngTears are replaced with piercing white blasts of light.: Overridden by Mom's Knife.

In-game Footage[edit | edit source]

Trivia[edit | edit source]

  • Added in Afterbirth This item is used in Challenge #26 (I RULE!).
  • In the original Binding of Isaac, buying the item from the Devil Room cost 1 heart container instead of 2.
  • The description of the item is a possible reference to the sniper's dialogue in Team Fortress 2.

Seeds[edit | edit source]

 PC  Added in Afterbirth † 8CKM J108 (Treasure room adjacent to spawn) Hard mode only

 PC  Added in Afterbirth † 6PG9 7RK3 (Treasure room up and to the right one room from spawn)

 PC  Added in Afterbirth DVNV YV9Y (Treasure room adjacent to spawn)

 PC  JW43 H8EK (Treasure room adjacent to spawn)

 PC  1M9E Y1G1 (Treasure room adjacent to spawn)

 PC  P8SE A9JW (Treasure room adjacent to spawn)

 PS4  S63T 434W (Treasure room adjacent to spawn)

 Switch  Greedier mode only JZCL 97JE (First Golden Treasure Room)

Bugs[edit | edit source]

Bug Bug! The Blindfolded condition also applies to the knives fired by Tammy's Head, and prevents it from working.

A butcher's knife.

Effects[edit | edit source]

Isaac wears Mom's dress.

Isaac will have his tears replaced by a single, penetrating knife. It can be shot diagonally by using two arrow keys (holding up and right will aim it diagonally for example.) It can also be used as an upfront melee weapon, in which case it does high damage and possibly instantly kills any non-boss enemies that its edge touches. The knife deals three times the melee damage when thrown, then two times when it stops, and same damage as melee when it comes back. On the other hand, the DPS is higher when using the knife as a melee weapon. Familiars will fire tears while the knife is charging.

Notes[edit | edit source]

  • The knife is tied to Isaac's base damage and shot effects (e.g. Spider's Bite).
  • A high tears stat will shorten the charge duration for the knife.
  • The distance the knife is able to travel is fixed at all times and therefore does not depend on the range stat. However, range ups will decrease the time it takes to charge the knife (similar to Tears).

Interactions[edit | edit source]

  • Brimstone, Dr Fetus - Mom's Knife overrides Brimstone and Dr Fetus with no special effect.
  • The Candle - If the Candle is activated while the knife is in mid-throw the knife will continue to move in a direction and speed that matches the movement of the player at the instant the candle was activated. The knife will continue to deal damage to whatever it touches and will return to the player as soon as the candle is used or deactivated. This also works with items such as Bob's Rotten Head or Notched Axe.
  • Technology - Mom's Knife overrides Technology with no special effect.
  • Technology 2 - Mom's Knife overrides Technology 2, with the 65% damage still applying to Mom's Knife, making this synergy not recommended. Although the Technology 2 laser will still appear to fire, it is purely cosmetic and deals no damage.
  • Mom's Eye - Mom's Knife completely overrides Mom's Eye if Mom's Eye is picked up after Mom's Knife
  • Wiggle Worm - The knife stalls in the air when thrown upwards or downwards and wiggles up and down when fired left or right.
  • Max's Head, Magic Mushroom - Mom's Knife does not stack with the 1.5x multipliers of these items or any other 1.5x multipliers.

Synergies[edit | edit source]

  • Certain tear affecting items also affect Mom's Knife, changing its color as well.
File:Knife the common cold.png The Common Cold
Tints the blade green and gives it a chance to poison enemies.
File:Knife number one.png Number One
Tints the blade yellow and makes it charge much quicker. The range down does not affect Mom's Knife in any way.
File:Knife the small rock.png Small Rock
Tints the blade grey and increases damage.
File:Knife a lump of coal.png A Lump Of Coal
Tints the blade black, but damage is unaffected.
File:Knife moms contacts.png Mom's Contacts
Tints the knife red and provides a chance to temporarily freeze enemies.
File:Knife spoon bender.png Spoon Bender
Tints the blade purple and gives a slight homing effect.
File:Knife ouija board.png Ouija Board
Tints the blade grey and makes it spectral. This synergy has no real effect on Mom's Knife, as it can already go through obstacles. However, this does make destroying poop and fires with Mom's Knife more difficult.
File:Knife sacred heart.png Sacred Heart
The blade turns white and deals much more damage with shorter recharge time.
File:Knife the parasite.png The Parasite
Turns the blade brown with no additional effects.
File:Knife spiders bite.png Spider's Bite
Tints the blade white and provides a higher chance of slowing enemies.
  • My Little Unicorn/VII Chariot - In addition to the damaging on touch effect, the knife does not disappear, allowing you to stab, throw the knife, and charge around at the same time, dealing high amounts of damage.
  • Pinky Eye - There is a 10% chance of the blade becoming poisonous (will appear green) upon entering a room.
  • Polyphemus - Greatly increases the damage of Mom's Knife without any effect on charge time. This synergy is strong enough to kill most bosses in under a second.
  • Mom's Bra - Isaac can deal high damage to any frozen enemy by simply standing near them, with little risk of being damaged himself.

Trivia[edit | edit source]

  • This item is based on the kitchen knife Mom took to sacrifice Isaac.
  • Firing Mom's Knife will still leave small puddles as if Isaac were still firing tears.

Bugs[edit | edit source]

  • As shown by the video below, The Candle with Mom's Knife makes the knife fly slowly toward that direction until it reaches the end of the wall or until you use the Candle shot.
  • Mom's Knife can sometimes float in the air aimlessly, even if it is not the candle glitch.
  • If the player has 3 Dollar Bill, the knife will have a randomized color in every room. If the player has homing tears (purple knife) for example, the knife could be red, too.

Videos[edit | edit source]

Related Achievements[edit | edit source]

File:MomsKnife.jpg "Moms Knife" - Complete Sheol with Isaac.


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