[Blink]

I might go for the skill of learning. I spend every day learning, it's what I do, and I enjoy it.

If I had to choose something less broad, I could choose a lot of things. Math is a good choice, but still broad. Programming is also super-broad.

At the moment, if you had me choose one tiny boring thing, I would probably get stuck and never answer. If you had a set time, I might say machine learning...

I could choose something stupid like "the skill of developing technology to physically remove and move my brain into an artificial internet-connected shell that allows me to live forever"...

I can't choose though.

---

I could choose something
However, then I'd have wasted all the time I've put into learning skills and things. What's the fun in that?

I'm already spending my entire life developing skills and trying to find a way to learn and live forever, this would be cheating.

Good thing this isn't real.