This could be a nice kata with a real description of the task.

Given any ball of the sequence, find the total score.

Current description looks to be ok.

The tests should be updated for Crystal 1.0.

you might use a sum instead of map method

i like your solution, but it seems that your isPrime function thinks 1 is a prime number.

OwO ?!!!!!

In the description, "Statistics URL:" has no URL after it, which appears to be a mistake.

Hi again...

• here is an example (not critical, but still) of why random tests should be fully random
• here is another example showing why nothing critical should be put in the preloaded section
• the problem with the two first batches of tests comes from the fact that you reverse the alphabet before rotating it, which is not said in the description (don't rely on the examples to provide specifications)
• the whole gentext function should be replaced with ''.join(choices(plainabc, k=randrange(50)))

Cheers

don't put spoiler flags on your answers when useless: only users who solved the kata can read your answer. Meaning... only you.

Hi,

• this has been done A LOT already, so I don't see what a new kata about ceasar chiper would bring up that could be interesting.
• the plain abc shown in the description is not the one used in the implementation, which is misleading
• the example in the description talks about a shift of 3 or -3 but the alpha are rotated of 2 or -2 only
• it looks like the Random Encode Positive Shift and Random Encode Negative Shift tests are wrong (Either I fail those entire batches and pass everything else, or the opposite. I might have missed somethign, tho... I just woke up...)
• the test suite should contain fixed tests as well

I strongly suggest that you unpublish the kata (because of "lack of novelty"). You can fix the problems if you want, but there are little chances the kata ever gets approved (I doubt it will ever reach the required satisfaction rate, because of the task/topic itself)

Cheers

• typos in description (chiper instead of cipher)