Analysis: Whatevermancy

Etymological Note

The suffixes -kinesis and -kinetic seem to have been naively derived from the well-known "telekinesis"; they actually mean "motion". Literally, "Hydrokinesis" would be the power to move water.

Similarly, -mancer and -mancy seem to have been derived from the well-known "necromancy", even though in the original Greek they come from the word manteia, meaning "divination". The "-mancy" template originally referred to the practice of divining the future using whatever the prefix was as a medium. So a classical necromancer would ask important questions of a dead person's spirit or read the entrails of a sacrificed (dead) animal, a pyromancer would look for important symbols in flames, and so on.

The proper suffix for someone magically manipulating a substance, force, or entity would be "-urgy" and "-urge" which derives from érgon or "work" - but, somewhat inconveniently for fantasy writers who want their magic to be spiritual or specially apart from the rest of nature, it's also the proper suffix for labor or manipulation of any kind, magical or not, such as surgery or metallurgy. (Or, yes, energy.) Consequently, "-mancy" and "-kinesis" are ubiquitous and "-urgy" is nearly unheard of, aside from the occasional "thaumaturgy" (literally, "wonder-working") as a fancier word for "magic".