Note: this tutorial assumes a basic familiarity with addballz and editing in LNZ Pro.
Because each breedfile has two lnz files - one for the baby and one for the adult - it is possible to make the two stages look very different. The base game has the baby petz be smaller, have bigger eyes and feet etc to look cuter, but we can take things even further. I used these techniques in my evolving pokemon breeds, and they could also be useful in breeds that need to grow features such as horns, wings, manes, etc.
Here's a simple example breed I've made. I've added a basic unicorn horn made from two ballz with a line joining them. To keep things clear (though not pretty), everything is a different colour - red for the base of the horn, yellow for the tip, and green for the line connecting them. You can make these addballz for your feature in LNZ Pro or Petz Workshop, whatever you prefer.
Now let's say we want to have the horn grow in as the dog grows. For that you'll want to go to your baby stage lnz - here GDPUP, as we're working with the Great Dane - and look for the section headed [Ball Size Override]. Most baby lnz should already have it, but if not, you can always add it in. The base dane puppy already has a few entries:
Puppy Ball Size Override section
You can read the LNZ Pro helpfiles to get an understanding of what this section does, but it's very simple - the first column is the ball number, and the second is the size. We've already given the ball a size in the adult's addballz section, but this will override that figure in the baby, hence the name. So put in the number for each ball in the feature (here 95 and 96), followed by 0.
Ball Size Override with the horn addball sizes set to 0
The puppy now comes out of the AC with no visible horn:
Puppy without the horn. (So a normal dog?)
And as the pet grows, the horn will appear:
Animation of the dog growing up
But that still doesn't look very good. As the horn grows in, it starts out as a thin line that thickens. It's not very natural looking. That's because all we've adjusted is the size of the addballz, but not the position. Fortunately, we can do that with a feature called [Add Ball Override]. This isn't commonly used, but it's a handy tool for this sort of hex. Most breedfiles won't have it, but you can add it in. Make sure it's spelled exactly as you see it here, or the game won't recognise it.
Again, you can read the LNZ Pro helpfiles here, but Add Ball Override allows you to override the position of an addball. We'll use it here to adjust the position of the horn tip (the yellow addball) so that it starts out at the base of the horn and grows outwards to its final position. We're only going to adjust one ball as the base of the horn (the red addball) is at the point where the rest of the horn grows from.
Add Ball Override takes four numbers. The first is the number of the ball whose position we want to adjust, here it's 96:
Add Ball Override with ball 96 listed
The next three numbers are the x, y, and z co-ordinates to move the ball to. We're going to use the co-ordinates of the horn base, which we can find in the adult lnz file's addball section. Rememember that the co-ordinates in the addball section are the second, third, and fourth columns. Here's the horn base co-ordinates:
Co-ordinates of the base addball
Now let's copy-paste them into the Add Ball Override section in the puppy:
Complete Add Ball Override section
Of course if you had more than one ball whose position you'd like to adjust, add each one on a new line, but here we're just changing one. Now, as before, the dog will come out of the AC without a horn and grow it in as it ages, but the growth should look a lot more natural.
Animation of the dog growing up
It's also possible to make paintballz change size between the baby and the adult. Using the same test breed as before, I've now added a big purple patch on top of the pet's back. Here's how it looks fresh out of the AC:
The same puppy with a patch on its back
Let's make it so that, like the horn, the patch is not visible at first and grows in as the pet ages. First, find the [Paint Ballz] section in the adult lnz, and copy it:
Copying the adult paintballz section
Now paste it all into the baby lnz:
the above pasted into the puppy .lnz
You can see that the paint ball I've created is at the top of the list, under the comment ";growable patch". Find whatever paintball you want to change, and look for the second column. This is the diameter of the paintball.
Change this number to whatever you want. I want the spot to be invisible in the puppy, so I've made it 0. You should now find that just like the addball features added earlier, the spot will grow in over time as the pet ages.
animation of the dog growing up, with both growable features
If you'd like to download the example breed created here to study how all this was done, click the link below: