[quote=@Ammokkx]
<Snipped quote by Xeiyenreisha>

I'm doing it like Komoney will be doing it: Mixing packs up. Like I did with the CE's in the previous booster pack, I put like a 3rd of them in there and the rest will be spread out over other packs. Or clockwork, I put in half there and the other half will come in the next pack. All custom archetypes will be split like this, though odd cases like Scarifar's Parshath support are going to have to be tossed in with the rest since I don't have enough cards of them to theme a booster around.
[/quote]

I'm guessing the rarity on those cards is high, correct? 

I mean, as I remember it clearly, the stronger the card and more powerful the effect the more rare and harder it is to pull.