Animal Companion advancement option?

Question

I rolled a Cavalier as a random class in a Skulls and Shackles game for a little extra excitement. Being a masochist I decided to roll with it, but took more than a couple optional rules/variants in order to make a class that's supposed to be about teamwork and horses work in a setting that's about pillaging and ships.

At the end of the day I ended up with a Human Cavalier using the Huntmaster Archetype, with an Osprey Animal Companion.

While looking through some min-max threads, I stumbled upon this one, which mentions an advancement variant whereby I could give my AC +2 DEX at level 4 instead of +2 STR:

How to create a useful bird companion?

While this option seems fantastic, I can't seem to find mention of it anywhere. Has anyone seen this option in the wild, and if so can you provide me a source?

Answer 1

The option is listed in the Animal Companions Description header:

As you gain levels, your animal companion improves as well, usually at 4th or 7th level, in addition to the standard bonuses noted on Table: Animal Companion Base Statistics. Instead of taking the listed benefit at 4th or 7th level, you can instead choose to increase the companion's Dexterity and Constitution by 2.