To my knowledge: with the right trainer/secret ID combination, any nature/perfect IV combination is possible with chained-shiny pokemon. The method is indeed more complex than the normal PV/IV algorithm [1]:

1) Proc a chained-shiny encounter,

2) Roll the PRNG twice to generate the initial PV (low word first, then high word),

3) Roll the PRNG thirteen times to mangle the top bits of the PV such that they are made shiny relative to the player's trainer/secret ID, and

4) Roll the PRNG twice to generate IVs.

The magic in step #3 happens thus:

1) XOR the trainer and secret ID to produce value

*T*,

2) For each bit

*B* in the range 3 through 16 (inclusive):

3a) Roll the PRNG once to get value

*X*, then

3b) If

*B* is set in

*T*, then

3b.i) If

*X* is odd, set

*B* in the low word, or

3b.ii) If

*X* is even, set

*B* in the high word; otherwise,

3c) If

*B* is not set in

*T*, then

3c.i) If

*X* is odd, set

*B* in both the low and high words.

In theory, the same algorithm could be run with minor changes (reversed checks) to force a non-shiny; one way to test this would be to take Wonder Card pokemon (which are allegedly always non-shiny) and to see whether the top thirteen bits are always set (since to me, that would be the easiest way to force a non-shiny).

Some more notable breakpoints:

**0x0205DED** Create chain set

**0x0205DF42** End of create chain set function

[1]: Credit goes to loadingNOW for the chained-shiny algorithm.

Where the fear has gone there will be nothing.

Only I will remain.