Talk:Championship/2018 McLaren X2/@comment-35307416-20181125145829/@comment-34918040-20181125162745

If you browse through the older comments, you'll see that many players were disappointed because they didn't get any engines at all from those Mini Boxes.

means that not even one of the three items inside a Mini Box is of legendary rarity. And then, Advanced Tech is also legendary, so your chance of getting an engine from a Mini Box is only 8,835 % (provided that Advanced Tech and CREs have the same probability).

This means that less than 1 out of 10 items will be a CRE. While the "regular" Championship boxes have a hidden guarantee for engines, the content of Mini Boxes is completely random.