--- NewSuperMarioBros hacking hint ---
Because NewSuperMarioBros is compressed, it is not possible to analyze it easily. 
Therefore, please use DeSmuME+hasteDS+ndsdis2. (Memory dump & disassemble)

*********** Attention ***********
I have only NewSuperMario(JAPAN Version). 
Therefore, the address and the value are different. 
YOU "Can Mario strengthen?"
I "He strengthens depending on your effort."

// Coin acquisition routine
:0201FE34 E59F103C ldr r1,[r15, #+0x3c]	;r15+0x3c=*(0201fe78)=#34122132(0x0208a994)
:0201FE38 E1A02104 mov  r2,r4,lsl #0x2 ;r2=0(0x0)
:0201FE3C E7910104 ldr r0,[r1,+r4, lsl #0x2]
:0201FE40 E3500063 cmp r0,#0x63 <<< "cmp r0,#0x63" has only little. 
:0201FE44 17910002 ldrne r0,[r1, +r2]
:0201FE48 12800001 addne  r0,r0,#0x1
:0201FE4C 17810002 strne r0,[r1, +r2]
:0201FE50 1A000005 bne 0201FE6C
(hack 1UP routine)Coin get -> 1UP!
0201FE50 1A000005 bne 0201FE6C -> 0201FE50 E1A00000 nop(mov r0,r0)
<CHEATCODE>
2201FE50 E1A00000

And,"ldr r1,[r15, #+0x3c]"(0x0208a994)->There are number of coins in address 0x0208a994. 
->0208A994 is hacking BaseAddress.

0208A944(-50h) Stock Item (00=Nothing 01=Mushroom 02=Flower 03=BlueShell 04=MiniMushroom 05=BigMushroom)
0208A97C(-18h) Mario x XX (BYTE)
0208A994(+00h) Coin (BYTE)
0208A99C(+08h) Score (WORD)

// Master code making
The "Master Code" cannot be easily made because it is compressed.

STEP1:Hack LZO routine
:020008E4 EB01F49E bl 0207DB64
:020008E8 EB00109E bl 02004B68
:020008EC EB01FA7B bl 0207F2E0
:020008F0 E59F1020 ldr r1,[r15, #+0x20] ;r15+0x20=*(02000918)=#33566720(0x02003000) << Mark point
:020008F4 E59FE020 ldr r14,[r15, #+0x20] ;r15+0x20=*(0200091c)=#-65536(0xffff0000)
:020008F8 E12FFF11 bx r1 (Jump to addr_02003000?) << "bx r1" = The interrupts point.
(Hack "bx r1" -> "b 0237C000" change)
(237C000-20008F8)/4-2 = DEDC0 = EA0DEDC0
<CHEATCODE>
220008F8 EA0DEDC0

STEP2:Look for the key input routine. 
:02043CF4 E59F1044 ldr r1,[r15, #+0x44]		;r15+0x44=*(02043d40)=#67109168(0x04000130)
:02043CF8 E59F0044 ldr r0,[r15, #+0x44]		;r15+0x44=*(02043d44)=#12287(0x00002fff)
:02043CFC E1D120B0 ldrh r2,[r1, #+0x0]		;r1+0xb0=*(040001e0)=#0(0x00000000)
:02043D00 E1D310B0 ldrh r1,[r3, #+0x0]		;r3+0xb0=*(02800058)=#0(0x00000000)
(--Omission--)
:02043D38 E12FFF1E bx r14 (Jump to addr_02043AA4?)
->DipStar is called from address 02043D38. 

STEP3:Examine the distance 02043D38->02002000.
(02002000-02043D38-8)/4 = FEF8B0 = EAFEF8B0

->":02043D38 EAFEF8B0 b 02002000"
Please make routine in 0237C000. 

STEP4:Write the hacking routine in 0237C000.
stmdb	r13!,{r0-r1}
ldr	r0,_KeyAddr
ldr	r1,_hackParam
str	r1,[r0]
ldmia	r13!,{r0-r1}
bx	r1
_KeyAddr:	.long	0x02043D38 << "STEP2" Key input routine "bx r14" address.
_HackParam:	.long	0xEAFEF8B0 << "STEP3" branch parameter.
<CHEATCODE>
A237C000 E92D0003
A237C004 E59F000C
A237C008 E59F100C
A237C00C E5801000
A237C010 E8BD0003
A237C014 E12FFF11
A237C018 02043D38 << Please correct it.  
A237C01C EAFEF8B0 << Please correct it.

STEP5:Specify residing DipStar ahead. 
<CHEATCODE>
C0000000 02002000
F237C020 E12FFF1E

Please match all the mastering codes. 

@Master code TYPE2(Fix crash bug)
A20008F8 EA0DEDC0 << Please correct it.  
A237C000 E92D0003
A237C004 E59F000C
A237C008 E59F100C
A237C00C E5801000
A237C010 E8BD0003
A237C014 E12FFF11
A237C018 02043D38 << Please correct it.  
A237C01C EAFEF8B0 << Please correct it.  
C0000000 02002000
F237C020 E12FFF1E

Please make Mario strong. ;)