How do I unlock the Base Athlon Helmet and Armor

Okay The Base Athlon Armor set my favorite armor in Halo 5, however I have no idea how to unlock it! It says it is a common Req card but i still have never gotten it, can someone tell me how to get it and if I have to get it in Req packs, which Req pack has the highest chance of giving it to me! I saw some stuff on wikipedia that says I have to be SR-19, which I am and I didn’t get it jn my promotion Req pack.

Just luck unfortunately. I think there are at least 3 different versions of it that are common so it should unlock eventually, I managed to get an Athlon chest the other day.

I would recommend spamming silver packs.

> 2533274904245048;2:
> Just luck unfortunately. I think there are at least 3 different versions of it that are common so it should unlock eventually, I managed to get an Athlon chest the other day.
>
> I would recommend spamming silver packs.

Thanks