The McKinsey Imbellus (or the McKinsey Problem-solving Game) definitely has made many rumors since its release because of its unorthodox appearance and requirements compared to the BCG Online Test and the Bain Online Test. Naturally, many consulting applicants have also wondered about the Imbellus’s difficulty level


This article will give a detailed explanation of the McKinsey Imbellus and its most challenging aspects in comparison with the other two main assessment tests from BCG and Bain. 

Overview of the McKinsey Imbellus

The McKinsey Digital Assessment is a simulation-based video game where candidates must act quickly with limited information to achieve a specific goal. Recruiters at McKinsey use the McKinsey Problem-solving Game (PSG) to determine which applicants have the qualities and abilities necessary to succeed in a position with the company.


The game assesses a candidate’s cognitive abilities in five fields

  • Situational awareness: Understanding your surroundings and the various responsibilities you have.
  • Metacognition: the consciousness of one’s mental abilities and thought patterns.
  • Critical thinking: examining a situation introspectively to draw a principled and sensible conclusion.
  • Decision-making: the ability to make a call only with the available data.
  • Systems Thinking: the capacity to identify the root cause of a problem and propose a realistic alternative.

The game’s format

The McKinsey PSG consists of six minigames, five of which are ecology-themed: 


  • Ecosystem Building 
  • Plant Defense 
  • Disaster Management 
  • Disease Management
  • Migration Management
  • Redrock Study (released in 2022)

Typically, only two of the mini-games are required of candidates, and the majority of the games given to candidates last for about 70 minutes. Each test starts with a brief walkthrough, then moves on to game scenarios that the candidate has to complete.


Ecosystem Building is the game that is played the most frequently, followed by Plant Defense. The other four minigames are considered alternatives for the Plant Defense game. 

The scoring system

According to McKinsey, the emphasis is on evaluating how candidates arrive at their solutions rather than just choosing those who provide the correct answers. It shows them “how you think and approach problems,” as McKinsey put it. So, test results will be determined based on two scores:


  • Product score: depending on each game that the “correct answer” will look different. But generally, it will be the number of animals/plants that survive at the end of each task. 
  • Process score: a numerical value calculated by an algorithm from observing a user’s mouse movements and clicks to deduce how they approach a problem.

Screen Examples of PSG’s Ecosystem Building Game 

The McKinsey Imbellus’s Biggest Challenges

Most applicants who have played the McKinsey Imbellus found themselves struggling due to two reasons: unpredictable assessment system and unexpected format.


As mentioned, results are decided based on two factors: product and process score. While it’s quite easy for candidates to estimate the former right after taking the test, the latter is still largely unknown. 


The format of The Problem Solving Game, a fully-rendered video game set in a natural environment instead of a business setting, marks a significant departure from virtually every other corporate selection strategy. Each minigame has a different set of rules, goals, and patterns; so it can be overwhelming for first-time candidates. 


Even though the games are broken up into different sections, you are only given a certain amount of time for each one, and you are not obligated to switch games if you find that you are spending too much time on one particular game. As a result, some candidates found themselves losing too much time on one game and having to rush through the other. 


In fact, although McKinsey’s decision to replace the written Problem-solving Test (PST) with the PSG was to welcome more applicants from non-business backgrounds, PSG’s pass rate is actually only 20–30%, lower than the PST’s 30–35%. 


McKinsey Imbellus vs. BCG Potential Test

The BCG Potential Test is an assessment test administered by the Boston Consulting Group (BCG) to evaluate an applicant’s numerical, verbal, and logical thinking abilities. There are two formats for the test: on paper and on a computer. 


The computer-based test consists of 23 questions that must be completed in 45 minutes. Each and every question relates to one single business case. The six major types of questions on the BCG Potential Test are:

  • Reading facts questions
  • Fact-based conclusion questions
  • Root-cause reason questions
  • Word problem questions
  • Formulae questions
  • Solution-finding questions

All of these questions, except for the last type, are very close to those on the McKinsey PST and can be answered with little to no business background at all. However, the BCG Online Test is still much more business-oriented than the McKinsey PSG. 

There are calculations involved in about 50% of the questions. This ratio is roughly equivalent to the McKinsey PST. On average, three calculations are required to find the answer to a math problem. But calculators are typically prohibited in the BCG Potential Test. The time limit per question is frequently reduced in offices that permit calculators. This means that success on the BCG Potential Test mainly depends on having strong mental math skills, while the McKinsey PSG covers a wider range of skills

Screen Example of BCG Online Test

McKinsey Imbellus vs. Bain Online Test

The Bain Online Test is a set of computer-based tests that Bain & Company uses to filter out applicants before an interview. The exam usually consists of 25–30 multiple-choice questions, which are answered in 30–50 minutes. Although named the “Bain Online Test”, sometimes in certain offices, candidates will still have to complete parts of the assessment in person.  


The Bain Online Test lineup normally includes these five types:

  • Aptitude Test
  • Personality Test
  • Analytical Test
  • Business Case Test
  • One-way Video Interview 

Fortunately, only 2-3 from these five types will show up in the real test. The main objective of the various tests is to evaluate your competency and character, not your knowledge. In this respect, you will be tested on your ability to analyze data, solve issues, and generate new solutions while working under time pressure.


The official branding of the Bain Online Test is that having a business background is not essential to pass the test. However, a lot of assessments are given in a corporate setting with limited time, so some previous knowledge is still needed.


Furthermore, while the McKinsey Imbellus are pretty much the same around the world, there isn’t a fixed format for the Bain Online Test. In contrast to the more well-known McKinsey PST, the “Bain Online Test” is not a standard test used by all Bain offices. Each location has a unique test creator, structure, and question categories. 


Luckily, the majority of assessments across various Bain offices have a similar structure and guiding principles. What this implies is that you may use the same basic strategy to go through each tests; unlike in the McKinsey PSG where each minigame has different rules and requires different approaches

Screen Examples of Bain’s Personality Test


To summarize, since McKinsey uses the Imbellus to recruit for various positions, not just for consulting, the ty[es of skills assessed in the test seems more comprehensive than the BCG Online Test and Bain Online Test. However, being a consultant now doesn’t only require cold hard analytical skills anymore, it also demands a more holistic approach. So the level of difficulty of the McKinsey Imbellus actually depends a lot on how you view consulting work.