When to stop using hoarded tokens for taco vault

Howdy. This post addresses the use of hoarding to maximize return on rare covers from vaults, particularly the taco vault. Hoarding allows you to apply saved tokens from past weeks to a single current vault (alternating between sweet and savory). Hoarding should only be done by players with well developed 3* rosters or better. If you're still transitioning to 3* land, hoarding is of little benefit to you because there are so many helpful covers that your odds won't shift much no matter how lucky or unlucky you get. On the other hand, getting your 3*'s covered as quickly as possible is most important so you should be using your tokens quickly, as long as you have roster space. Or maybe even if you don't have roster space and need to choose which characters to roster, but that's a different topic.

On the other end of the spectrum, for some vets, like Pongie below, the taco vault is primarily a great source for health packs and covers become almost a secondary bonus. In that case, you're really hoarding your tokens until you need health packs and then using them as needed. I tend to go this route. I stop as soon as I get 1 or 2 sets of health packs because I hate having more than 10. Since health packs regenerate, having more than 10 is kind of wasteful.

For players well along the 3* transition, more and more pulls end up being disappointing duplicates of covers you don't need. Therefore it becomes important to try to maximize your chances of getting something you'll actually be able to use. The taco vault increases your odds every time you pull garbage, but if you get something good, subsequent odds are actually worse. So if you have hoarded tokens, it's better to stop to let the vault reset if you get lucky early. This only really matters if you've hoarded enough tokens to make a difference. At low numbers of tokens, the change in odds is fairly insignificant. If you do hoard a lot of tokens, it's best to wait until you see a vault you like, then keep drawing and not get discouraged until you get something you wanted because the odds keep improving until you get it.

Below is a spreadsheet indicating where the stop points are located based on how many things you want, how many you've gotten, and how many tokens you've already used. Does not take into account varying levels of goodness (ie a 4* vs a needed 3* vs HP) as that's up to you to decide.
Left row is the number of items in the vault you would actually want.
Top row is the number of "good" items you've already drawn out of the vault.
Spreadsheet body indicates number of draws below which indicates you've had good luck and above which indicates you're getting rid of garbage and the vault is helping you.

As an example, say there are 20 items in the vault you would be happy with keeping. You use 18 tokens and get nothing, but on number 19, you get something you wanted. 19>16 so you're still behind on the odds and should keep going. You use 3 more tokens and get another good result. 22<31 so you should stop. For the next 9 tokens, your odds are actually worse than for a fresh vault. Time to go back to hoarding.



Edited post to answer some of the below comments.