McKinsey Solve 2025: Seawolf Deep Dive

This article is a deep-dive into the Seawolf mini-game of McKinsey Solve. All insights are up-to-date for the latest 2025 version.

Please read the main article on the McKinsey Solve (2025 edition) if you haven’t done so.

Overview of McKinsey Solve: Seawolf

3rd game in McKinsey Solve

Seawolf is the third game in the McKinsey Solve suite of 2025, where it is placed after the Ecosystem and Redrock games. The candidate must finish both Ecosystem and Redrock before they can access the Seawolf game.

Unlike all the “alternative mini-games” that appeared since 2020, Seawolf has not replaced any current game in the Solve suite; its deployment in McKinsey pre-screening round marks the first time the Solve test consists of three games instead of the usual two.

Your job is to clean up ocean sites

In Seawolf, your job is to clean up a number of ocean SITES. (currently three). Each site is contaminated by a different kind of waste, which must be treated with a different TREATMENT. Each treatment is composed of three MICROBES, which must be suitable to the requirements of the sites.

Because of this “plot”, the game is also commonly known as “the Ocean game”, or “Ocean Clean Up”. In this article, we use the name “Seawolf”, which is official and stems from the name of the research ship you are in charge of in the game.

Time limit is 30 minutes

The time limit for Seawolf is fixed at 30 minutes. Even if you complete Ecosystem and Redrock early, the remaining time won’t be carried over to Seawolf.

Within those 30 minutes, you are free to allocate whatever amount of time you want between the three sites (i.e. if you finish one site early, the remaining time will be carried over). All tutorials are untimed, as with most McKinsey Solve games. 

Unlike Ecosystem and Redrock, however, time management is a significant issue in Redrock. We will look at this issue in more detail in the later sections.

Key concepts in the Seawolf game

Microbes, with their attributes and traits

In each Seawolf session, you will have to work with dozens of microbes (84, to be exact). Each microbe is defined by its CHARACTERISTICS, which consist of:

• Attributes: Each attribute is a quantitative characteristic, with values being whole numbers from 1 to 10. Known names for attributes are Energy, Adhesion, Speed, among others. Each microbe has 3 characteristics.

• Traits: Each trait is a qualitative characteristic. A microbe either has a certain trait, or it doesn’t. There is one trait for every microbe. Known names for traits are: Heat-resistant, Aerobic, Hydrophilic, Bioluminescent, among others.

Microbes in Seawolf do not use real names; instead, they use nonsensical names like Cyro Virus, Ops Amoeba, etc., presumably to not cause any unnecessary assumption on the candidate side and influence their problem-solving process. Likewise, the icons are pure made-up.

Each microbe and its information is displayed using what we call a “microbe card”

Sites, with their attributes and traits

In each Seawolf session, you will go through three sites. Each site is defined by its REQUIREMENTS, which correspond to microbe characteristics and consist of:

• Attributes: site attributes are always ranges, such as “1-3”, “4-6”, “9-10”.

• Traits: each site has two traits: one DESIRED trait and one UNDESIRED trait.

Unlike microbes, sites don’t have names or icons. In-game, they are only referred to as “Site 1”, “Site 2”, Site 3”, etc.

Steps in each site, and the flow of the game

To clean up each site, a candidate must go through four or five steps, depending on the site as well as their actions in previous sites. Those steps are:

• Step 1 - Build microbe profile: during this step, the candidate is to choose two characteristics (1 attribute and 1 trait, or 2 traits, or 2 attributes) to create a preferred profile. Actions in this step do not affect any other step (or site).

• Step 2 - Categorize microbes: during this step, the candidate is given 10 microbes, and must decide whether to use them for the current site they are in, reserve them for the next site, or reject the microbe entirely. This step does affect Step 0 of the next site. 

• Step 3 - Build prospect pool: during this step, the candidate must build a “prospect pool” of 10 microbes, of which 6 microbes are already given. To select prospects, the candidate goes through 4 selection rounds, in which they must select 1 in 3 candidate microbes. The prospect pool created in this step will be used in Step 4 of the same site.

• Step 4 - Create treatment: during this step, the candidate must choose 3 microbes from the 10 prospects chosen in Step 3, to form a “treatment”. The treatment must adhere as close as possible to the efficiency rules, and achieve 100% efficiency if possible. The treatment created in this step does not affect any other step or site. 

• Step 0 (of next site) - Review microbes: during this step, the candidate must choose 3 microbes from the 10 prospects chosen in Step 3, to form a “treatment”. The treatment must adhere as close as possible to the efficiency rules, and achieve 100% efficiency if possible. This step affects the Step 2 of the same site. 

Of these steps, Step 0 can only appear in Site 2 and Site 3. The remaining steps are consistently present in all three sites. Each candidate must go through all the steps of one site before moving to the next site.

How score is calculated

In-game efficiency rules (Step 4)

Efficiency calculation rules are stated twice in Seawolf, once at the beginning and once at the start of Step 4 in the tutorial. The rules are as follows:

• Default clean-up efficiency of a treatment is 100%. If the treatment misses any of the following criteria, it will receive a deduction on its efficiency:

• All mean values of attributes for that treatment must stay within the site requirement range. If any attribute mean value falls out of range, the treatment receives a 20% efficiency deduction. The maximum deduction from this criterion is 60%.

• The treatment must contain at least one microbe with the desired trait. If this is not met, the treatment receives a 20% efficiency deduction. The maximum deduction from this criterion is 20%.

• The treatment must not contain any microbe with the undesired trait. For each microbe with the undesired trait, the treatment receives a 20% efficiency deduction. The maximum deduction from this criterion is 60%.

The scores of your treatments in Step 4 are usually referred to on prep sites as “product scores”, which can be easily measured / calculated by candidates themselves, because they are directly related to the completion of quantifiable objectives.

Note here that for attributes, it’s the mean values from all microbes that counts. So if you have a microbe that has an attribute falling out of range, that attribute is still usable if you pack it up with microbes that balance it out. Keep this in mind because you will see it again in the “suggested approach”.

Examples of efficiency rules

Example 1

Example 2

Example 3

Process scores in other steps

Because efficiency is only calculated in Step 4, the scoring mechanisms in other steps (1, 2, 3) are left unexplained by McKinsey. We do know, however, that McKinsey measures “process scores” which are based on your behavior in the test.

Below are our educated guesses on these process scores:

• They will value consistency in approach, between and within each step. For example, in Step 2, if you reject one microbe, then accept another microbe with similar characteristics, it will be perceived as inconsistent. Inconsistency suggests lack of structured mindset, which is a crucial requirement for a consultant.

• Your approach should be consistently based on efficiency rules. Even if those rules only apply to Step 4, in all other steps you have to act as if following those efficiency rules. This will let McKinsey know that you are an objective-driven person, exactly the kind of person they want. 

Suggested approach

Before we continue, let’s talk about how we should approach each step. McKinsey wants to see consistency, and they want us to be objective-driven.

So the suggested approach for Seawolf, in all steps, is to establish a set of clear-cut, preferably quantified criteria, with which you can use to divide all microbes into groups.

These groups are different in how much a microbe “fits” with the site. The microbe should be deemed “unfit” only if it is completely unusable. 

We can then use these groupings to filter out all unfit microbes, which, by our estimation, takes up 60-70% of all microbes. 

Step 1: Build microbe profile

Objective

In Step 1, you will build a microbe profile by choosing 2 target characteristics (either 2 attributes, or 2 traits, or 1 attribute and 1 trait). Use the site information on the right side of the screen to find out which characteristics you must choose.

Interface explained

The interface in Step 1 contains a site card, containing information of the “current site” (that is, the site you are working on) on the right hand side, and a profile setting panel on the left hand site.

On the profile setting panel, you can “turn on” two characteristics by clicking on the switch besides their name. Turning on a characteristic means telling the system that you prefer to see those characteristics in your microbes. You have to turn on two switches before you can confirm and move on to the next step. As long as you have not submitted the result, you are free to change your selections.

Each attribute on the left panel is also accompanied by a slider, with two values - these are the min and max values of that attribute for that profile. 

Carry-over rules

Despite the tutorial talking as if setting a certain profile here will affect the microbes you will be given in Steps 2, 3 and 4, it’s not true. According to our customers who have taken the steps, the profile set in this step will not influence the next steps.

This is actually reasonable: it would be extremely punishing if McKinsey makes the test in a way that even a small mistake at the start would ruin everything thereafter. 

Tips for this step

Step 1 is simple: all you need to do is choose the hardest-to-meet attribute AND the desired trait, then set the range of the hardest-to-meet attribute to match the range on the site. 

What is “hardest-to-meet?” If an attribute has a narrower range, or it is more offset from the center, than the other attributes. Let’s look at a few examples:

Step 2: Categorize microbes

Objective

In Step 2, you will categorize 10 microbes to the current site you’re cleaning up, or to the next site, or to neither site (Reject). You cannot change your categorizations once decided. If you categorize a microbe to “next site”, you will review that decision when you move to that site.

Interface explained

On the right side of the screen, the information card for the current site is still there with full information, but it is now supplemented by another card for the next site, with one characteristic displayed, which can be a trait or an attribute.

On the left side, there is now a microbe card. It is followed by three buttons, each of which represents a category option (current site, next site, reject). If you click on these buttons to categorize your microbe, the game will ask for your confirmation.

If you confirm the category, then the microbe card is moved into one of the three categories in the center of the screen. You can still see the names and information of your categorized microbes here, but you can no longer change their category.

Carry-over rules

This step does not affect Step 3 and 4, but it does affect Step 0 of the next site, and by extension, Step 2 of the next site. More specifically, if you choose to categorize a microbe as “next site”, it will appear again in Step 0 of the next site, asking if you want to keep its categorization.

Tips for this step

The most crucial tip for Step 2 is to always prioritize the current site. Ask first if a microbe can be used for the current site; if the answer is a resounding and absolute “no”, then and only then can you ask if the microbe can be used for the next site. 

Likewise, you should prioritize using a microbe for the next site over rejecting it. You should only reject a microbe if including it in your treatment will surely result in an efficiency deduction.

Step 3: Build microbe profile

Objective

In Step 3, you will complete a pool of 10 prospects for use in Step 4. 6 out of 10 prospects are already given to you. To choose the remaining 4 prospects, you will review 3 candidate microbes at a time, and select only one of them. You cannot change your selections once decided.

Interface explained

On the right side of the screen, the site information card is ever present. The remaining part of the screen is divided into two sections: (1) the half-built prospect pool, and (2) potential candidates to fill it up.

Both sections consist of microbe cards, but the prospect pool will feature “minimized” versions of those cards, with the names of characteristics hidden. In the real test, the legend to help you read the minimized cards will be at the bottom right of the screen.

If you choose to add a candidate microbe to the prospect list, the game will ask for your confirmation, like in Step 2. Once you’ve confirmed that decision, there will be no going back.

Carry-over rules

This Step 3 does not just “affect” Step 4, that’s a great understatement. The prospect pool you build in Step 3 decides how much efficiency your treatment can reach in Step 4.

Tips for this step

The approach for Step 3 is to “categorize” the candidates according to whether they fit into the current site, and then choose a best among the fit ones (or the least-bad, if all candidates are unfit, which seems to happen a lot in this step).

In many cases, there is only one fit candidate, so you don’t really need to choose. If you do need to choose, then you have to be flexible about it. Skim through the given prospects and see if you can find any patterns, and choose accordingly. 

For example, if you see no or very few desired-trait microbe among the given microbes, you will need to prioritize candidates with that desired trait; or if you see most given microbes leaning towards the low end of an attribute, you will need to prioritize candidates with high values for that attribute to balance out.

Step 4: Build microbe profile

Objective

In Step 4, you will select 3 prospects from the prospect pool you created in Step 3, so as to form a treatment. The treatment will be used to clean up the current site, with its efficiency calculated using “clean-up efficiency rules”.

Interface explained

The interface of Step 4 is nearly identical to Step 3, but reversed: you still have the prospect pool, but now you use it to fill up the treatment selection.

You are free to add and remove microbes until you are ready to submit; in this regard, Step 4 is more forgiving than the previous steps. Not that it really helps much.

Carry-over rules

Step 4 does not influence any other step or site. 

Tips for this step

By this time, if you have already categorized all the microbes in Step 3, it should be easy to spot the best possible treatment. Simply rule out the unfit microbes, and work only with the fit ones. Microbes take up only about 40-60% of all microbes, so there are often just 4-6 fit microbes by Step 4. 

Keep in mind that in many cases, there is no 100% treatment. Such cases seem to happen at a rate of about 30%. In such cases, you can make do with a 80% treatment and move to the next site, and be careful not to over-commit your time.

Step 0 (next site): Review microbes

Objective

In Step 0, you will review the microbes categorized to the current site during Step 2 of the previous site. You can choose to keep them for Step 2 of the current site, or reject them.

Interface explained

The interface in Step 0 is nearly identical to Step 2, except it no longer has the “next site insight” (because this is now the next site, and information revealed in full).

The microbes already categorized to “next site” in Step 2 of the previous site will now re-appear on the left side of the screen, with the options for you to either keep that initial categorization, or change your mind and reject the microbe.

Carry-over rules

The microbes you “keep” will reappear in Step 2 of that site, but already categorized, and you can’t change its category. Besides that, your actions in Step 0 will not affect Step 2 (or any other step).

Tips for this step

Approach this Step 0 the same way you do with Step 2. It’s normal and almost expected that candidates change their categorizations for microbes upon learning the full requirements of the site, so don’t be afraid to do it and it should not affect the results of the previous Step 2.