@@KingRalph
STR is a ARM function that is used to store values in memory, When u have a function like str r0, [r1, #0x99], what the computer does, is it grabs the value of r0, and stores it into R1 at the address 0x99 in memory. Changing the address to 0x0 (0) will without a doubt cause a crash, as the program would be modifying section of memory that probably doesn't even exist. Same goes for NOPing an STR, sooner or later, some function will try to access the amount stored at the register at the memory address, and crash, since the value is not present. When we hack, we changes R0 to another register so when the program stores the values, it will store a higher value from the other register, into a register at a memory location, which could hold currency, energy, health, damage, stats etc etc.