Is your feature request related to a problem? Please describe.
A gene with a requirement of flight that allows phasing through blocks. Perhaps with a keybind option similar to dragon's breath or teleport. I'm seeing the Vex as a good vanilla mob candidate for it, but maybe you'll have some others in mind.

Some do, like ender dragon health. Noclip is much more useful than flight, it would need some kind of limiter, I think

Ok, I think I see what you're saying. No idea what the crafting recipe would be, but maybe a "quantum tesseract" or something that you have to be holding similar to the dragon health crystal?

Good idea, I like it! I wonder how I'd implement it. Maybe a material cost too, since that's pretty powerful.

Do any other ones currently have a material cost? If I'm not mistaking, that would be a rework of the current system? Also, when you say how to implement it, are you speaking from a players perspective or in the Java?