I might be stupid but

[Sharluker]

Can we be told how some attacks work? I beat the demo a couple times now and I have minimal complains but I saw someone do some sick air slash projectiles on a yt vid and somehow can't figure out how to do it .

[Kaiser]

That attack requires:
At least 1 pip of energy
The Heavy (red) sword equipped
For you to be in the air, and hold the attack button.

Easiest way to get enough height to make sure you have time to let the attack take its course is to slide -> high jump -> hold attack