Any addition to the description is unnecessary, It's up to you to understand the requirements given and come up with an approach.
Any further corrections are based on the comparison you make with the results from the test/attempt tests.

TLDR: Solving on CW is TDD oriented.
closing.

The kata is nicely challenging, but the instructions are incomplete and it is difficult to understand what the exact conditions to put '■' are.
How was I supposed to know that '■' must be put in place of Max and then (Max - 1) over each next line? From the sample tests it seemed like it should be in place of a maximum number of each line.
Much time wasted.
Please correct the instructions and make samples with numbers with difference more than 1 between them.

No worries!

It was published with Node v12.x, which does not need describe. This breaks Node v8.1.3, which does require it. I do not consider that a problem. Get with the times.

You're right, my bad I should have checked that. I solved this kata quite a long ago and the test page remained on the old version. Thank you and sorry for then inconvenience.

There's a bug in your code.

Are you on a legacy version? Try selecting Node v12.x.

have you updated JS tests lately

He probably did, but he doesn't understand that the correct structure is describe -> it -> assertions, so his edits broke everything - not sure how he managed to publish it at all this way.

Johan I'm not sure to understand, have you updated JS tests lately? If so, they seem broken, see issue at the top of the page.

JavaScript tests (both basic and attempt) crash:

Test Results:

"it" calls must be invoked within a parent "describe" context

STDERR
/runner/frameworks/javascript/cw-2.js:237
          throw ex;
          ^
"it" calls must be invoked within a parent "describe" context

I have problems too, but it seems different from you. I don't know if it's related.
Edit: Well, I don't think it is. I think your code needs some debugging, check input, output, analyze log messages... See there: https://docs.codewars.com/training/troubleshooting

There seems to be an issue with JS version. Sample and all random tests are fine, but fixed test shows an error "expected 100 to equal 0". Can't wrap my head around how it is possible. Can anyone help?