system
Given the following post, respond as if you're commenting on Reddit:
human
[Avatar The Last Airbender] What types of subbending could still be discovered?

We know bloodbending, lightning bending, metalbending, sandbending, plantbending, lavabending, icebending, and probably some others. What other types of subbending could be developed besides these?
gpt
Weather-bending, from either air or water, is an obvious one. Steam-bending is specific, but logically follows from water and ice bending.

Based on the idea that fire-bending is more strictly energy-bending (it also controls lightning and explosions, after all), light-bending is a logical next step for that, and sound-bending makes some sense for air-bending (what is sound but air vibrations?).

Bloodbending might expand into other bodily fluids (yeah, yeah, get your jokes out the way) and maybe, with study, become full on body/flesh bending. The human body is mostly water, after all...