User blog:Tecku/Tecku Talks: Card Pack Value

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So, if you don't know, today's daily challenge in PvZ: Heroes is impossible. PopCap is using the same Puzzle Party from last year but didn't take the nerfed Medula Nebula into consideration, making it literally unbeatable. Maybe PopCap will give us a bonus pack for this error. Speaking of which, what is the value of a pack, anyway?



Tecku Talks About: Pack Value

Value of an Average Pack

This post will use some math to determine the average spark generation rate per pack. For starters, let's calculate the average value of any given pack, ignoring elements such as getting new cards, the small chance of unlocking a Hero, and bonuses from multipacks. Each pack has a guaranteed Rare card, a 30% chance of getting a Super-Rare card, and a 10% chance of getting a Legendary card. These values are independent of each other as well, so there is a 3% chance of getting both a Super-Rare and a Legendary card.

Assuming we get all duplicates, the spark value is calculated as the chance of each card occurring times their value:

  • 50- (One Rare card)
  • 45- (at least Three Uncommon cards)
  • 75- (0.3*250 chance of hitting the Super-Rare)
  • 10.5- (0.7*15 of getting an Uncommon)
  • 100 (0.1*1000 chance of hitting the Legendary)
  • 13.5- (0.9*15 of getting an Uncommon)

This adds up to about 294 sparks in the average pack of cards, assuming all are duplicates. However! If we are saving our Gems and spending them on multipacks, this number jumps up to 323.4. That means that if we save our Gems up, every group of 100 Gems becomes worth 323.4 sparks.

Factor: Non-Duplicate Cards

Now we have the value of an average pack. However! This number increases the more incomplete our collection is. If rather than getting a duplicate Legendary, we get a new Legendary, we can assume that the card is worth 4000 points instead of 1000. This, of course, means that the value of the packs (are by extension the Gems used to buy them) become worth more.

Let's assume that we have all Super Rares, and are only getting new Legendaries. Since the odds of getting a new Legendary change over time as our collection fills, we shall assign it a variable. In this case, we will use the letter L to stand for the odds that a Legendary will be new. Most of the values in the above calculation stay the same. However, the lines for hitting the Legendary is replaced with these new lines:

  • 100-100L (0.1*1000*(1-L), where L is the chance that a Legendary will be new)
  • 400L (0.1*4000*L, where L is the chance that a Legendary will be new)
  • 13.5- (0.9*15 of getting an Uncommon, stays the same)

This means the value of 100 Gems put into a pack is 294+300L, where L is the fraction of Legendaries you have yet to max out. Add the multipack bonus, and we get 323.4+330L instead. The calculation including Super-Rares is 294 + 225s + 300L for regular packs and 323.4 + 247.5s + 330L for multipacks where s equals the percentage of desired Super-Rares and L equals the desired percentage of Legendaries.

Examples on Using the Formula

Don't understand how to use the formula? Let me give an example.

Here's another example. Suppose you buy a regular pack of Premium cards and have four of every card except for Expresso Fiesta, Dandelion King, Octo Zombie, and Zombot Sharktronic Sub.

  • s = 1/40 (Since you need 1 type of card out of the 40 Premium Super-Rares)
  • L = 3/30 (Since you need 3 types of cards out of the 30 Premium Legendaries)
  • Thus, the formula becomes 294+225*(1/40)+300*(3/30). This gives you a value of 329.625, or 362.5875 when bought in a multipack.

Here's another example. Suppose you buy a regular pack of Galactic cards and have four of every card except for Tactical Cuke, Moon Base Z, Onion Rings, Shooting Starfruit, Binary Stars, and Space Cowboy.

  • s = 2/30 (Since you need 2 types of cards out of the 30 Galactic Super-Rares)
  • L = 4/20 (Since you need 4 types of cards out of the 30 Galactic Legendaries)
  • Thus, the formula becomes 294+225*(2/30)+300*(4/20). This gives you a value of 369, or 405.9 when bought in a multipack.


Cost Analysis

So, let me ask you: when does it become more efficient to buy Legendaries for decks outright instead of buying packs?

First, let's calculate what the value buying Legendaries outright is. For this case, we'll assume you already have all the Super-Rares for your collection. Legendaries are worth 4000 sparks and cost 1150 Gems when bought outright, so the spark value is 347.826 per group of 100 Gems. In order for it to be more efficient to buy cards outright, this value must be more than the previous bonus. Thus, 347.826 <= 323.4 + 330L. Plug that in and we get the 0.074 <= L.

If the fraction of Legendary cards you want comprises less than of 7.4% of the Legendaries in the pack, it is more efficient to buy them outright. Otherwise, your better bet is to buy multipacks.

Cost Analysis Examples

Let's give an example: say you really, really want a Dark Matter Dragonfruit, no matter what. Dark Matter Dragonfruit comprises 5% of Galactic Legendaries, so it's better to buy it outright.

However, say you want a Dark Matter Dragonfruit OR a Supernova Gargantuar. These make 10% of all Galactic Legendaries, so it's more efficient to buy the packs.

This also means buying multipacks is more efficient than buying cards for Triassic Triumph and Colossal Fossils outright since they can only go to a minimum of 10% chance for a single Legendary.



So, yeah. Hope this is helpful!