Sound 2: sound banks with random/generative variation
The basic technique of making an independent Godot scene that represents a sound bank, with the ability to randomly play a file from the bank by calling a function, was already demonstrated in the Sound 1 area of technical practice.
To demonstrate level 2 sound you would just go beyond the Sound 1 expectations, without necessarily introducing anything new in the way of "Godot technique". Specifically, the expectation for level 2 is that you would go further in terms of really making and using (randomly/generatively) larger banks of originally recorded/originally synthesized sounds (e.g. distinct footsteps, distinct collision sounds, etc) that are randomly triggered in convincing/meaningful ways during game play. (By contrast, in level 1 there was no expectation that the random/generative sound events in the game came from originally recorded/synthesized sources, and nor was there any expectation that they be particularly numerous.) If anything about this expectation is unclear, please reach out and ask about it!