Estimating Value of Loot Chests Based on Rewards Probabilities

I had acceptable results in my last few attempts of last-day rental strategy despite my trial-and-error approach. At face value, I didn't gain much at all. I only had a few dollars of net profit after deducting rental expenses.

Even so, I wanted to keep doing it. There's wild fun in anticipating what comes out of the loot chests. And this last-day rental strategy almost doubles the chest count compared to what I'd normally get. Rather than focusing solely on gains, I'm now looking at both the fun factor and the potential rewards.

What I'd recommend though, is to minimize your expenses as much as possible so you won't feel that bad when you get a lousy pull from chest rewards. In this post, I'll try to give some practical tips to gauge whether you may be spending too much on last-day rentals. And if you have zero clue of what a one-day season-end rental is, check out my "How to get 10+ Extra Rewards using Peakmosters" blog for a step-by-step approach on how to do it.

First, Let's Uncover the Chest Loot Probabilities

The actual reward you'd get from chests is defined by specific probabilities. Common monster cards, potions, and small amounts of DEC are the likeliest of all the rewards to come out. On the other end, gold cards and booster packs are the least likely to appear.

We should consider these probabilities to determine how much DEC is okay to spend on last-day rentals to temporarily buff our league rating. It's best to avoid instances where we're spending way too much more than what we could gain on average.

That does sound incredibly hard. BUT! We don't need to do any math since the genius @tehox has already developed a tool to show us the data we need (Thanks, @tehox! Don't know you personally but you seem like a great, talented guy. You're the best! 😎):

Loot Chest Value Calculator


Take note that you must change the League setting to the exact League you're aiming for. Each league level has different probabilities for each type of reward. Higher leagues have better odds of giving out the best among all reward options. I am targeting Diamond III League so I've set mine as such:



Again, each league has different probabilities, so the estimated value of a loot chest is dependent on which league you are at when the chest was opened. Let me give a specific example of the drop probabilities between Gold League III (the league I'm at without rentals) and Diamond III (the league I'm targeting). All these data were drawn from the loot chest value estimator too.

Potential Reward	Gold III Drop Rate	Diamond III Drop Rate
Potions	24.00%	23.25%
Booster Pack	1.00%	1.75%

I have excluded drop rates for DEC and card rewards since it remained constant between the two leagues. The only difference lies in Potion and Booster Pack probabilities. In Diamond III, I have slightly fewer chances of getting potions and slightly higher rates of getting packs.

The 0.75% increase may not look like much at first glance, but if you consider it more deeply, you'll see a significant difference in rewards potential. That 1.00% drop rate spells a "very likely" one booster pack out of 100 chests you open. While the other 1.75% is a "very likely" one booster pack out of 57 chests. I say "very likely" because nothing is guaranteed. The RNG may still screw you over if it hates you that much.

Second, Let's Put a DEC Value to these Loot Probabilities

If you're still with me and you're getting the idea of chest probabilities, let's now take a look at how those probabilities affect the estimated value of the chest. Luckily, it's all there in the tool, so we don't need to do actual calculations. To better understand the concept, let's jump right into the abridged version of the estimated DEC value of chests per league.

League	Estimated Chest Value (DEC)
Bronze I	27.5 DEC
Silver III	36.2 DEC
Silver I	42.9 DEC
Gold III	46.2 DEC
Gold I	52.9 DEC
Diamond III	56.2 DEC
Diamond I	62.9 DEC
Champion III	66.2 DEC
Champion I	72.9 DEC

The Estimated Chest Value (DEC) field is the current value indicated in the loot chest estimator. Note that these values are not static since card market prices and DEC-to-USD conversions are constantly changing. Looking at the table, it's very obvious that as we go higher in leagues, the loot chest's potential value grows too. All these relate to the fact that higher leagues have better odds of getting the good stuff.

Third, Let's Compute Our Rental Expense Baseline

I went through the previous topics as a backgrounder for estimating how much DEC is good to spend on last-day rentals. It's a lot of info, but, hopefully, it's not that difficult to digest. Also, the tool already does most of what we need so we don't need to know every detail that's happening behind the scenes.

Here's the actual, simple calculation we need:
Good Rental Expense = Loot Chest Estimated Value x Expected Extra Chests


Good Rental Expense is our rental cost baseline. Ideally, our actual expenses will be much lower than the calculated 'good'.

Loot Chest Estimated Value is the value provided by the tool for our target league. At the last day of the previous season, Diamond III loot chest had a 63 DEC estimated value.

Expected Extra Chests is the total extra chests you can gain by jumping into a higher league. The difference between the season-end rewards from my current league (Gold III) and target league (Diamond III) is 18 loot chests. And then, I'm adding 4 more to the count from the extra chests I will gain from at least one Daily Quest. The extra chests I'm getting totals to 22 at the least.


In practice, that's 63 DEC x 22 chests = 1,386 DEC. If my total rental expense for my season-end power boost is anything below 1,386 DEC, then I'm good.

How Did My Season-End Rental Go?

The rental expense baseline is most useful for a retrospective review of your strategy. It's primarily meant to help you determine if your previous methods worked or not.

It would be amazing if we could maneuver our actual rentals to fit our expense target. But it's very difficult to apply it in-process due to the fast-changing market prices, especially on the last day of the season. I've seen rental prices double in a span of a few minutes on season-end. It's extremely hectic and unpredictable.

For the last season-end that happened a few days ago, I was able to rent for Power at a relatively cheap price. But, honestly, even if prices had shot up and doubled at that point, I would have still pushed on, willing to spend way more than my planned rental expense. I wouldn't want to get stuck in between leagues, so there's no way for me but to move forward no matter the cost.

But what happened was nothing complicated; it was a simple and straightforward rental process that was completed within four hours after I placed my bid. I spent 870.125 DEC (2.65 USD) which was a lot lower than my 1,386 DEC baseline.

_{My Rental Stats taken from Peakmonsters.com}

Thus, in terms of the estimated average value of the loot chests, I got a winning rental deal. Now, let's take a look if I have real gains based on what I actually got from the chests.

But on a sort of tangent point, let me show you first these amazing cards that I rented

I let Peakmonsters do the renting for me through the CP Bid feature, so I can't control which specific card I'm getting. Thus, it's always a pleasant surprise if I manage to acquire a strong card that I could actually use to win battles.

Power:	75,000 CP 🤯	25,250 CP 😎	26,250 CP 😎
Cost:	500 DEC 😱	126.32 DEC 😉	156.20 DEC 🤗

Love these glorious babies, especially Ruler of the Seas. Don't mistake this section for the actual rewards that I got. I'm only RENTING them for a day. However, what I did get wasn't too shabby, and won't lose out to these epic monsters.

To End, Was my Rental Worth it based on Actual Rewards?

Before I get into guesstimates on my gains, let me reiterate the idea that the last-day rental strategy not only (a) increases chest rewards, but also (b) increases the quality of ALL chests. I only realized about the "quality" aspect recently. My jump to Diamond III league meant that I'm less likely to get potions. That alone is a major advantage.

As for my rewards, here's a screenshot of the best loot I got among the extra 22 chests.


And here's the calculation of my expenses and gains. The gains listed here are at a minimum, and actual values should be much more since I haven't quantified the "quality" improvement for ALL my chests. I only factored in the extra 22 loot that I got.

Expenses	DEC	USD($)
Needed CP Rent Cost	-870.13	-$2.61
Rewards Value
DEC	55	$0.17
Potions	-	$0.24
Djinn Biljka Card	-	$4.09
Djinn Oshannus Card	-	$2.93
All Other Cards	-	$0.56
Booster Packs	-	$0
Total Rewards	-	$7.99
Net Gain	-	$5.38

So far, this is the season that I had the most gains from the last-day rental strategy 😁 I got slightly more lucky with the rewards and with the cheaper rentals. Now that I'm getting the hang of it, I'll probably do it more in the coming seasons 😅