The feat extra evolution states the following:
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Extra Evolution
Your eidolon has more evolutions.
Prerequisites: Eidolon class feature.
Benefit: Your eidolon’s evolution pool increases by 1.
Special: You can gain Extra Evolution multiple times, but only once for every five summoner levels you possess.
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The Improved Natural Armor evolution states:
Improved Natural Armor (Ex)
An eidolon’s hide grows thick fur, rigid scales, or bony plates, giving it a +2 bonus to its natural armor. This evolution can be taken once for every five levels the summoner possesses. Source: Advanced Player's Guide
FAQ
Errata for Improved Natural Armor:
The description of the evolution says, "This evolution can be taken once for every five levels the summoner possesses." Unfortunately, that text is unclear. A summoner can select this evolution once for levels 1—4, again for levels 5–9, a third time at levels 10–14, a fourth time at levels 15–19, and a fifth time at level 20. This wording will be clarified in the next update document and print run for the APG.
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What's the minimum level for a summoner to take the extra evolution feat twice given this similar wording and the current errata? Can he use his level 5 feat to take the extra evolution feat a second time?
I tend to think it was clear even without the errata...
yes, he can use his 5th level feat to take extra evolution a second time. And yes, you could use that point to imp natural armor each time.
The only reason that I ask is because there is a number crunching player in my group, who has been arguing against my character since the game has started and I just want to make sure that I have solid ground to stand on when I say, "Yes it does work like this. Do you want me to show you in the book?"
The other interpretation is "Level 1-5 you take the feat 1 time, then level 6-10 you can take the feat again. " If this happens then the next available feat to take imp evolution is acquired at 7th level.
Yep.
I was going to post this very same thing on the Hero Lab forums as a bug, since it's scripted to allow the second Extra Evolution no earlier than 10th level.
As such, I've been unable to convince my DM of this very point, since even HL has it wrong.
Thanks for reminding me!