How many hours in shards does a purple skin cost?
An 'epic' or purple skin is $10 actual dollars. How much in game time does it take to grind the shards out to buy that same skin?
I've bought a couple skins here and there, but now that I'm playing all the killers $10 per skin is just nutso and I don't play nearly enough to ever complete a rift on time. If I could go back and complete the rifts whenever, I'd buy those battle passes but as it stands I just don't have enough free time to grind that out.
I tend to save my bloodpoints to characters I actually play, so most of the survivors I choose not to level and just grab the perks as they show up with the shrine, so I don't have many shards as it is.
Answers

It depends on how much XP you get each Trial. I recommend playing Killer for grinding Iridescent Shards since you normally stay in a match longer as a Killer.
Provided each of your matches has a duration of 13 minutes, it would take approximately 106 hours to get a very rare outfit.
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I heard that you basically need a whole devotion level to earn a full purple outfit (About 100 Player levels)
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Ok so on average you get 0.072 shards per exp. (according to DBD wiki)
each exp point is 1 second of ingame time. Purple skins cost 7200 shards soooo
7200 devided by 0.072 equals 100000 (seconds) or roughly 27 hours, 46 minutes and 40 seconds.
However this was only factoring in gametime. If you want to minimize Playtime you should only play two games a day and get the daily killer and survivor bonuses of 300 exp for each.
this is way harder to exactly calculate but lets just say each game takes about 10 is minutes~ and you fully max out the exp counter at 500 each round (oh yes you can only get 500 exp per round)
Soo 0.072 times 800 to get the ammount of shards per game = 57.6
7200 / 57.6 is equal to 125 what means you would need to play 125 games
with the current estimate of an average game being 10 minutes you would need 1250 minutes or around 20 hours and 50 minutes flat.
So Tl;dr
You will need roughly 21 hrs to 28 hours for 1 part of a purple cosmetic set.
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