I was able to finish the eco-system in time and felt a pen and paper were perfectly fine. I think the time is not really the calculations as they were very simple, but the matching of species. Therefore I don't think an excel would be much of help but rather it will limit you. For the eco-system, keep this in mind: 1) The species have 4 environment characteristics (Temperature, soil PH, .. etc). There are not so many variations of these so you could easily notice that all species can be grouped in 2-3 categories. You will notice that very quickly. 2) Start by choosing plants which are fed by sunlight or waste. I chose 3 ones which have a lot of calories to give and have the same characteristics. The list wasn't too big (maybe 7-8 different plants) and again, you will easily notice how they can be grouped. 3) then, I chose the 1st level predators which are essentially the ones mentioned in the plants descriptions as their predators (total 4 but I excluded one of them because it needed more calories than the plant they feed on. 3) Then I chose 2nd level predators (total of 2, the ones that feed on the 1st level predators). Same logic, choose the ones that need an amount of calories which the 1st level predators can provide. 4)Then, test the system. On your paper, decide which animal eats first. The plants don't eat so focus on the animals. The animal with highest calories PROVIDED eats first. Draw the 1st eating process and check if the animal/specie fed on will have above zero calories. Then it's successful. Then the next one with 2nd highest calories provided and so on. My total processes were 5 as I had 5 animals. 5) The time for the 2nd game is much more than what you need. I was recommended by the game to spend 30 mins on 3 rounds (10 mins each) but that's way too much than what you need. You will not need more than 5-6 mins per round so feel free to use a bit of extra time for the eco-system on the expense of the 2nd game. Best of luck :)

Hi there, addressing your question: I A/B tested with my mentees using pen and paper vs Excel, and using the Excel should save you approximately 5 minutes during the game. The reasons are: (i) you can copy/paste instead of writing everything; (ii) you are going to be more organized and won’t get lost in your notes. Besides the Excel, the McKinsey Imbellus Game Secrets guide will also offer you (i) Template to organize the food chain (ii) The exact rules to follow for the Ecosystem Management (there are 7 and you should be aware of all of them) (iii) Examples of Chains working and not working so that you can practice in advance. If you have other doubts please feel free to PM, I will reply within 12 hours. Best

Great report! Do let us know if you passed.

I failed the test for the analyst role and didn't get interview invite then, so probably a pre-requisite (could differ from location to location?)

Thanks for the feed back. Are you the same person as the poster above or the OP of this thread? Also did you feel you performed well in the game? And hence surprised by the regret mail. I made a big mistake by not considering eating rules. Really worried. Also how long did It take for you to get the regret mail? Thanks

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