[2020] Heiloom rarity

Hey @SomeChoccyMilk. 

I'm afraid I don't have the exact number other than <1% chance to randomly pull heirloom shards from a pack. From personal experience, it's pretty rare. 

The system is set up so that you are guaranteed to receive the shards after you open 500 packs if you haven't randomly pulled them. If you open that many packs without ever getting the shards, you'll see them once you open pack number 500. 

/Kent