difficulty TRIVIAL TO SUPER HELLDIVE

TrivialEasy
Trivial → EasyPlatform
Which front
How it is delivered

Trivial, Easy, Medium, Challenging, Hard, Extreme, Suicide Mission, Impossible, Helldive, Super Helldive. A difficulty is only available once the one below it has been cleared, which makes this a ladder rather than a list and means the climb has to be done in order.
The first eight unlocks are a couple of dollars each. The step from Helldive into Super Helldive is roughly as much as all of them put together, and that is an honest reflection of the gap: it is the difficulty most of the playerbase never clears, and it is the one that gates super samples.