I completed this kata in Ruby but hated it. Here are my issues:

• Why did the levels switch from perfect squares to not?
• Why did gold move from the top level in 1 through 4 but the fourth level for 5, the third level for 6, the second level for 7, etc.?
• Why is the parameter called "level" and can go up to 15, but there are never more than 4 levels in the answer hash?

Maybe if I had played Minecraft before, I could have solved this kata without using a kind of brute force case statement. I feel as if there was not enough detail in the description. Plus, nothing I Googled explained how the beacon tower needed to go beyond the four basic levels (9 to 25 to 49 to 81 blocks) only that you could make the tower shorter.

I feel like I wasted a couple of hours of my time with this kata and that it was more like a level 3 or 4 kata.

it "should raise an error for string with illegal characters" do
  Test.expect_error(luck_check('6F43E8'))
end 

is obviously wrong - can't catch an exception that has already happened. that needs to be in a block. still strange that it doesn't complain when it doesn't raise when that's what it says it tests for. doesn't really matter though, unless this also happens for MRI 3.0.0

For some reason, I was getting an error message that my Ruby code was not throwing an error when I pushed "Test" although my code had this line: raise ArgumentError, "string with illegal characters" if str.empty? || str.match?(/\D/). By commenting out this line, the test passed. However, it wouldn't pass when I pushed "Attempt". So, I removed the # to uncomment the error line before pushing "Attempt", and the code was accepted.