SN Defense is a memory patch that protects your character from old-school Null Overflow attacks (e.g., enemies using null.st files with massive state controllers in statedef 140140140 or similar). It blocks them from instantly killing you by overwriting your Alive flag.

Note: Automatically on character selection.

Side effects:

1. May crash on first select (just reload and try again).

2. Jank vs "Varexp" or advanced nulls (expected).

3. Breaks reloaders (auto-revive exploits) and your own SN edits.

4. Can cause stuck animations (fix below).

Let's begin...
Get the SN Defense .st File
Or, this one if the 1st doesn't work

Extract the attached Freeze.7z (5.32 KB).

Inside: freeze.st (pulled from "Absolute Zero Hard" char – name doesn't matter).

Place it in your character's folder (e.g., chars/yourchar/freeze.st).
Then, add DtC Patches

In your character's CNS file → Scroll to [Statedef -2] (bottom of file).

Copy-paste these exact states (they exploit DtC to write to memory):
[state -2]

type = displaytoclipboard

trigger1 = !ishelper

text = "%.*d%n%d"

params = 0, 0, 4932696

ignorehitpause = 1

[state -2]

type = displaytoclipboard

trigger1 = !ishelper

text = "%.*d%n%d"

params = 0, 0, 4932697

ignorehitpause = 1

[state -2]

type = displaytoclipboard

trigger1 = !ishelper

text = "%.*d%n%d"

params = 0, 0, 4932698

ignorehitpause = 1

These patch specific ram locations (hex: 0x4B4458–0x4B445A) to block overflows. skip = instant crash!

Now...last step
Load char in WinMUGEN.

Select → May crash (retry).

Fight a null cheapie (e.g., one with null.st & 140140140 state).

Null hits → You survive (no instant KO)!

If you run into any issues remember, to keep in mind these fixes:

1. Stuck animations - SN messes with common1.cns. Copy Statedef 0 (Stand) & Statedef 20 (Walk?) from data/common1.cns to your main CNS (override them).

2. First select crash - Normal. Exit to menu, reselect.

3. Crashes vs nulls - Expected jank. Test vs KFM first.

4. Reloaders broken - Intentional – SN Defense kills revives.

Remember, as said in the previous tutorial if you run into issues join the discord and people will try their best to help.

So in this tutorial, well guide. I will be explaining how a strong tier mugen cheapie function and then provide a copy/paste template you can use on your desired character. Note: this works for all versions of mugen but I recommend using this on 1.X

So yes no different from some video tutorials. but now this is in written format. let's begin...

A strong (強) tier cheapie is a character that often possesses techniques with higher performance than those of ordinary ranks. these are characters who have very difficult AI, have devastating attacks and can chain attacks consistently. Most of these can have their AI tuned down, though that has started to become a lot less common. They have the potential to be evil or even mad. but after this tutorial here's to hoping they are more common :D

Examples of chars who are of this tier are, Magic Geese, Omega Tiger Woods 2012, Kevin (Seiken Densetsu 3), and Ryuko 2nd. Credits to Unbyte for providing these examples.

Now that you got an understanding of how they work, here's now a copy/paste template you can add unto a .cns file of your desired char (or on a fresh .cns file)

Strong Tier Template

As per usual, if you run into any issues, you can join the discord OR submit a feedback form. 

This is just bonus content for, if people want specific codes and tips along with information to add unto their chars. all sources that the information was obtained from will be cited. :D

Let's begin...

Want your character to have maximum power at all times?
[statedef -2]; This must be done in this section.

; Copy and paste this section below.

;---------------------------------

[state -2]

type=poweradd

trigger1=roundstate=0

If you don't like value=powrmax;max, you can adjust the variable to an integer.

;--------------------------------

; Just put this code into the statedef -2 section.

Want characters to have colorful invincibility?
[State]

]
type=lifeadd
trigger1=!ishelper
trigger1=palno=[7,10]
trigger1=numhelper(7400)=1
trigger1=helper(7400),gethitvar(damage)=[-1000,500]
value=-ceil(helper(7400),gethitvar(damage)/2)
ignorehitpause=1
[state ]
type=lifeadd
trigger1=!ishelper
trigger1=palno=[11,12]
trigger1=numhelper(7400)=1
trigger1=helper(7400),gethitvar(damage)=[1,300]
value=-5
ignorehitpause=1
[state]
type=varset
trigger1=!ishelper
trigger1=MoveGuarded
trigger1=numenemy
trigger1=!(enemynear,movetype!=H||enemynear,ctrl=1)
var(9)=enemynear,gethitvar(hitcount)
ignorehitpause=1
[state ]
type=varset
trigger1=!ishelper
trigger1=numenemy
trigger1=(enemynear,movetype!=H||enemynear,ctrl=1)
var(9)=0
ignorehitpause=1
[state ]
type=varset
trigger1=!ishelper
trigger1=numenemy
trigger1=!(enemynear,movetype!=H||enemynear,ctrl=1)
var(4)=enemynear,gethitvar(hitcount)-var(9)
ignorehitpause=1
[state ]
type=varset
trigger1=!ishelper
trigger1=numenemy
trigger1=(enemynear,movetype!=H||enemynear,ctrl=1)
var(4)=0
ignorehitpause=1
[State ];Round
type=varset
triggerall=!ishelper&&alive&&roundstate>1
trigger1=sysvar(2)!=0
trigger2=(var(58)!=-1&&var(58)=var(57))
trigger3=(var(56)!=-1&&var(56)=var(55))
trigger4=(var(54)!=-1&&var(54)=var(53))
trigger5=(var(52)!=-1&&var(52)=var(51))
trigger6=(var(50)!=-1&&var(50)=var(49))
trigger7=(var(48)!=-1&&var(48)=var(47))
trigger8=(var(46)!=-1&&var(46)=var(45))
trigger9=(var(44)!=-1&&var(44)=var(43))
trigger10=(var(42)!=-1&&var(42)=var(58))
trigger11=fvar(10)!=0
trigger12=fvar(11)!=0
trigger13=fvar(12)!=0
trigger14=fvar(13)!=0
trigger15=var(24)!=0
trigger16=var(25)<0
trigger17=var(26)<0
trigger18=var(27)!=0
trigger19=var(30)!=0
sysvar(2)=1
[state ]
type=lifeset
triggerall=!ishelper
trigger1=sysvar(2)!=0
trigger2=numpartner&&roundstate>2
trigger2=partner,alive||lose=0
value=lifemax
ignorehitpause=1
[state ]
type=PalFx
triggerall=!ishelper&&alive
triggerall=GameTime%30=0
trigger1=sysvar(2)!=0
add=0,0,0
sinadd=200,200,200,30
time=30
ignorehitpause=1
[state]
type=selfstate
trigger1=!ishelper&&alive
trigger1=sysvar(2)!=0
trigger1=stateno!=150
value=150
ignorehitpause=1
[state ]
type=selfstate
triggerall=!ishelper
triggerall=roundstate<4
triggerall=sysvar(4)!=gametime+gametime*2+gametime*3-gametime*4
triggerall=sysvar(2)=0
trigger1=time>1200
trigger2=time>300&&roundstate=3
value=52
ignorehitpause=1

If you write it like this, the character's body will change into different colors and become invincible.

If you want to add a feature that throws an invincible reflection while defending here,

[state ]
type=selfstate
triggerall=!ishelper&&alive
triggerall=roundstate<4
triggerall=sysvar(4)=gametime+gametime*2+gametime*3-gametime*4
triggerall=sysvar(2)=0
trigger1=time>2000;
trigger2=(var(17)=[1,5])&&(stateno=[5000,5200]);trigger
value=52
ignorehitpause=1
[state ]
type=selfstate
triggerall=!ishelper
triggerall=roundstate=4
triggerall=sysvar(4)!=gametime+gametime*2+gametime*3-gametime*4
triggerall=WIN
triggerall=alive
triggerall=sysvar(2)=0
trigger1=stateno!=180
value=180
ignorehitpause=1
[State ]
type=selfstate
triggerall=!ishelper
trigger1=stateno=512
trigger1=sysvar(4)=gametime+gametime*2+gametime*3-gametime*4
value=120
ignorehitpause=1

[State ]
type=selfstate
triggerall=!ishelper
trigger1=alive=0
trigger1=sysvar(4)!=gametime+gametime*2+gametime*3-gametime*4
trigger1=time>100||roundstate>3||(numpartner&&roundstate=2&&var(29)=0)
value=5050+100*(pos Y>1)
ignorehitpause=1

[State ];Round state
type=varset
triggerall=!ishelper&&alive&&roundstate>1
trigger1=sysvar(2)!=0
trigger2=(var(59)<1)||(var(17)!=[0,1]);Round?Round state Lv
trigger2=stateno!=[0,1]
trigger2=stateno!=[10,12]
trigger2=stateno!=20
trigger2=stateno!=40
trigger2=stateno!=45
trigger2=stateno!=[50,52]
trigger2=stateno!=[100,101]
trigger2=stateno!=[105,106]
trigger2=stateno!=[110,111]
trigger2=stateno!=120
trigger2=stateno!=[130,132]
trigger2=stateno!=140
trigger2=stateno!=[150,155]
trigger2=stateno!=170
trigger2=stateno!=175
trigger2=stateno!=180
trigger2=stateno!=190
trigger2=stateno!=[200,203]
trigger2=stateno!=205
trigger2=stateno!=400
trigger2=stateno!=[402,404]
trigger2=stateno!=[600,605]
trigger2=stateno!=[700,701]
trigger2=stateno!=[800,801]
trigger2=stateno!=[803,804]
trigger2=stateno!=[900,901]
trigger2=stateno!=920
trigger2=stateno!=2000
trigger2=stateno!=2200
trigger2=stateno!=[3500,3502]
trigger2=stateno!=[5000,5001]
trigger2=stateno!=[5010,5011]
trigger2=stateno!=5020
trigger2=stateno!=5030
trigger2=stateno!=5035
trigger2=stateno!=5040
trigger2=stateno!=5050
trigger2=stateno!=[5070,5071]
trigger2=stateno!=[5080,5081]
trigger2=stateno!=[5100,5101]
trigger2=stateno!=5110
trigger2=stateno!=5120
trigger2=stateno!=5150
trigger2=stateno!=[5200,5201]
trigger2=stateno!=5210
trigger2=stateno!=5500
trigger2=stateno!=5900 trigger3 = var(22 )
>6;? ... trigger4=enemy(0),alive||enemy(numenemy>1),alive; sysvar (22)>12;13 trigger5=numenemy trigger5=(enemy(0),life>enemy(0),lifemax*0.95)||(enemy(numenemy>1),life>enemy(numenemy>1),lifemax*0.95); trigger5=anim=2211&&animtime=0; sysvar(2)=1

You can just put this code together.

Sources for these 2 codes: https://www.mugenassociation.com/TABLE13/4

Want Crazy Red's %n code?
Red's %n

Want to know how to use the most powerful supernull code that is "Direct Fire?"
This system is a large and highly complex implementation.

Direct Fire represents the highest tier of Super Null behavior. At a sufficient scale, can overwhelm virtually any character. however, this level of power introduces significant stability risks if not handled correctly.

While some characters may not require helpers or variables, this implementation intentionally uses both to maximize control, consistency, and safety. careful adherence to the structure is strongly recommended.

Compared to %n-based systems, Direct Fire builds demand a higher technical skill level and deeper system awareness.

The Direct Fire engine operates through layered defensive and control logic:

1. State fixation locks the character into controlled execution.

2. Multiple variables and helpers maintain state integrity.

3. Self-movement continuously spawns helpers and variables.

4. This creates a high volume of null triggers.

5. Nulls interfere directly with the opponent’s life system.

6. The opponent’s alive state becomes corrupted (e.g., 255 or -2).

7. A forced KO is finalized.
   
   

This chained execution is what delivers overwhelming effectiveness.

This code operates at an inherently high risk level.

Incorrect implementation can destabilize mugen itself, not just the opponent. Crashes, freezes, or forced shutdowns are possible if safeguards are not properly tuned. Thorough testing and controlled deployment are mandatory.

On modern systems, performance impact is typically manageable, but instability should always be treated as a realistic operational risk.

For now, only use defensive codes in the -2 code! Among them, use state fixation methods, not selfstate avoidance methods!

[state -2, death]

type = selfstate

trigger1 = 1

value = 5150

ignorehitpause = 1

Like this and just paste common.cns into the def file! 

[statedef 5150]

hitdefpersist=1

[state]

type=statetypeset

trigger1=1

statetype=S

movetype=A

physics=N

ignorehitpause=1

[state]

type=attackdist

trigger1=1

value=0

ignorehitpause=1

Please put it in exactly like this. And leave about 12 helpers [if you want to kill them more surely, you should leave more than 12] and make the helpers be summoned with the code 5150 And put in several variables.

[state] 

type=displaytoclipboard

trigger1=!ishelper

text="alive:%d, lose:%d, numH(1):%d, numH:%d, eH:%d"

params=alive,lose,0,numhelper,enemy,numhelper

ignorehitpause=1

[state]

type=displaytoclipboard

trigger1=!ishelper&&numhelper(89011)

text="alive:%d, lose:%d, var(0):%d, numH:%d, eH:%d"

params=alive,lose,playerid(helper(89011*!!numhelper(89011)),id+numhelper(89011)-1),var(0),numhelper,enemy,numhelper

ignorehitpause=1

You have to use helpers and adjust them to program like this. 

[state]

type=selfstate

trigger1=ishelper(89011)

trigger1=id=helper(89011),id+numhelper(89011)-1&&hitpausetime

trigger1=var(0)=4&&roundstate<3+2*!var(3)&&playeridexist(root,id)+numenemy+numpartner

trigger1=var(0):=6

value=5158

persistent=256

ignorehitpause=1

 Configure the SelfState as follows:

• Helper ID: This can be any number, as long as it matches the helper you previously created.

• Variable number: This can also be any value. Choose a number that does not conflict with your existing variables.

Next, adjust the number of null executions inside each state:

• In [StateDef 5151] through [StateDef 5162], set the null count to at least 600–1000 per state.

Once configured, use SelfState to transfer execution into those states.

That’s it.

Run a test and verify whether the opponent is defeated. Your own HP does not need to decrease as long as a KO is triggered, the setup is functioning correctly.

This concludes the setup. source: https://www.mugenassociation.com/TABLE36/30

I know some of you are probably wondering why I am taking a good chunk of info from this site. well it is because it is in korean and, it provides a lot of useful info. 

If you understand korean you're good, but if you don't it's best to translate when going on the site. they provide a lot of good coding and this is just the tip of the iceberg. 

Note: The address for this tutorial's Alive content is for the Windows version. Please adjust the address to 557-560 for RC. 

Ensure a high success rate for the technique. 

Note 2: Operation of the perpetual principle and freeze super-instant death principle is required. 

Ensure a high success rate for the technique.
Note 3: This technique requires operation on units that can perform p2stateno. If they cannot, it is invalid!

Template link

Remember, you gotta have a good idea at this point on how to do frozen super instant death throw to understand this. 

This is based off of this video tutorial from bililbili

Note 4: If you don't understand chinese, don't have an account, and can't follow because of how BLURRY AF the video is. you can get the HD tutorial here

Kosen stuff (or more accurately spelled "kōsen" / "kosen" in romaji) in the context of MUGEN almost always refers to a Japanese term for extreme "cheap" characters, supernull characters, nuke characters, or engine-crashing exploit characters, basically the most broken, unfair, glitch-abusing creations in the MUGEN scene.

So as you can tell the coding provided in this pack of "kosen" stuff is for authors that like to add deliberate engine-breaking weapons to their chars for example, they consists of the following:

• Instantly kill the opponent in 1 frame (or before the match even starts properly)

• Freeze/crash MUGEN

• Corrupt memory

• Exploit WinMUGEN/1.0/1.1 bugs like:

• Variable index overflow (var(999999999))

• PalNo overflow / tampering

• HelperID / ParentID corruption

• Statedef -1/-2/-3 overflow loops

• %f format string exploit (arbitrary code execution)

• DLL search order hijacking (UltraNull style)

• Zlib exploit / executable disintegration attempts

The tiers/layers you listed earlier (Alpha → Nu, with things like "Forced Executable Disintegration", "Absolute Freeze", "Helper Obliteration", ".cns Obliteration") are exactly the classification system used in the Japanese/Chinese cheap character scene for ranking these from "basic instant death" up to "full engine nuke / possible process hijack".

Famous examples of "kosen-tier" characters

1. Infinite Soulabyss (hypernull / top-tier)

2. Undefined Universe (UU — often uses DLL tricks)

3. L_Reimu variants

4. The Will of Hades / Demise / Prison Flame edits

5. ONI-MIKO-R, Crazy Catastrophe, KillAll (Supernull)

6. IFEnd (early MessageBox + auto-close exploit)

7. Various "zlib exploit" or "UltraNull" loaders

Now that you know what it all means..you should now understand If so says "that's some real kosen shit", they mean it's ridiculously broken and unfair even by cheap character standards. (which tbh dont take my word for it i dont even know anyone that really says that only just saying the word cheap lol)

Link to the Kosen Stuff

I think with the amount of information presented here..it's time for a bit of a rest stop.

While, we are here. I would like to present you some extra tips assuming you are have went this far into being a mugen cheapie author. if you're still new to everything that's fine these tips will still apply.

So, let's start off with 1...

Tip 1 - 

You do not have to follow the crowd. meaning, you do not have to make the 1000th donald edit, touhou edit, kof edit, melty blood edit, etc...you can explore other options that is YOU want. in fact, for example if you love marvel. there's TONS of marvels characters that you can edit. it's interesting because, you can make for example. Spiderman a ultranull or, Iron man a null. pretty neat right? or, you see a pretty cool OC? no problem, edit them to your liking. mugen is free and infinite. you can be creative and your creative can be endless. (although doesn't mean you can make things that people frown upon such as fetish content though especially, if you want people to actually care about your works or if you want your works taken a lil bit seriously)

Tip 2 - 

Define success before you start. know what “done” looks like so you don’t spiral into endless feature creep. get a stable v1 out, then optimize. momentum beats polish paralysis.

Tip 3 -

If you are lost on what new concept or, unique idea on what to use on your im assuming not 1000th donald edit, you can take a look at this document here for it gives you some ideas and such. best part is, you make a char with any of ideas, people will be intrigued of your works. 

Another, document you can check is here  for it's the same thing, but a bit more ideas you can use. 

Hi, so in this post I will be providing you guys to a very useful discord for anyone who is in the japanese side of the mugen community or really, anyone who is interested. this server is filled with mugen cheap authors, they also post their characters there as well as well as their other works and coding examples.

 So, if you want to go to a rabbit hole and willing to use a translator or you understand japanese to an extent I recommend joining. https://discord.gg/pbsym9zMDJ