Welcome to a world of adventure and magic...
Golarion One
With the popularity of Multi-Versal Physics, we can explicitly define our universe as an alternate Time Line: "Golarion One" where in 4719, second edition Pathfinder did not come into effect. Multiverses are infinite, this story is ours.
Warning: Homebrew Houserules
There are a few, mostly minor rules changes to Rules-as-Written (RAW) Pathfinder, which we will publish as we go. But the first thing to mention is the Trompe-d'Oleil, a poorly priced crafting template that (after some adjustment), will serve to make our Big Bad Evil Guy - The Game-Breaking Painter Wizard.
The Trompe template purports to let a sufficiently skilled crafter create a magic painting of any creature in the game. There are some downsides, mostly relating to the constructs psychology - these are not "real" creatures, and if they believe themselves to be, they will turn evil and kill to "earn their place". They should have a mechanical tendency to go crazy, although this is left to GM discretion.
In our universe, some changes are to be made, starting with specific training/research to be completed, such as by studying from the Tome of Trompe. Upon a brief review of contruct immunities, we can include immunities for bleed, disease, death effects, necromancy effects; but not include immunities for paralysis, poison, sleep effects, and stunning. Trompes do not breathe, eat, or sleep, but they must be healed with Make Whole, Fast Healing or similar, and "are destroyed" at zero hitpoints, activating their rejuvenation power.
Trompes in Golarion One world can be subject to ability damage, ability drain, energy drain, fatigue and exhaustion, but not nonlethal damage.
Also, the crafting prices, both for size (which don't scale right), and for HD, are too low. Let's fix this right now:
I am fine with Medium being a 2000g base, but then Large is 8000g, Huge = 18000g, Gargantuan 36000g and Colossal (5x5) would be 50,000g. This is just math, painting materials cost do not "scale" anything but linearly.
We should also raise the Price/Cost per HD by four times, to 4000g/2000g.
Finally, the DC for crafting Trompes will be 15+[HDx2] (plus additional modifiers where appropriate).
Yes creating Trompes will be an exploit, something The Painter Wizard uses to bend reality to his will. But no, a 5th level character cannot paint a great old one, no matter how much he munchkins.
The Painter Wizard has been expelled twice now from Golarion One, his current whereabouts unknown but believed to be under the protection of one or more Arch Devils, perhaps part of Asmodeus' grand plan.
He has documented much on his experiments with the psychology of Trompe's, and while much of his earlier works have either been destroyed or gone mad, some say he has unlocked deeper secrets of managing these strange magical contructs.
Stay tuned for more information from our universe.