Overwrite's a MethodInfo's JITed assembly code so that a method aways returns false.

evil.cs

private static void ChangeToReturnFalse(MethodInfo methodInfo)
{
    var intPtrConstructor = typeof(IntPtr).GetConstructor(new[] { typeof(void*) });
    var method = new DynamicMethod("ChangeToReturnFalse", typeof(IntPtr), Type.EmptyTypes, typeof(ServiceLocationModule));
    var generator = method.GetILGenerator();
    generator.Emit(OpCodes.Ldftn, methodInfo);
    generator.Emit(OpCodes.Newobj, intPtrConstructor);
    generator.Emit(OpCodes.Ret);
    var addressFunctor = (Func<IntPtr>)method.CreateDelegate(typeof(Func<IntPtr>));
    var address = addressFunctor();
    var x64Asm = new byte[]
    {
        0x33, 0xc0, 0xf3, 0xc3
    };
    var x86Asm = new byte[]
    {
        0x55, 0x8b, 0xec, 0x33, 0xc0, 0x5d, 0xc3
    };
    var asm = IntPtr.Size == 8 ? x64Asm : x86Asm;
    Marshal.Copy(asm, 0, address, asm.Length);
}