With magic in my worlds I usually start out with a foundation built on scientific principles, sometimes mixed with psychological phenomena that can easily seem supernatural, and then expand from there until it becomes a new kind of science altogether - which is what magic basically is in The Prophecy; a self-invented science - with laws and principles of its own, some derived from how we know the world in our time of advanced technology and knowledge and some derived from the faulty perception of the world that beings from medieval times might have had, or at least have in the Planes. Shien might have mentioned this, but one of the Laws of Magic in this universe - the sixth of them and coincidentially my favorite and most correct one among them - is "change never exceeds what you know". Magic in this universe is based on science, but exists as an extension of the will and mind of the creature who uses it. Thus even though the ability to "disrupt molecular structure" with sound makes a certain amount of sense from our point of view, it's not possible to do with magic in this world because the beings therein have no knowledge of molecular science, or even the existence of molecules. At the current level magic only really materializes its effects on macro-level, and the effects produced will adhere to the mistaken expectations its user has to these.
That being said, using this Echoer-ability you describe does sound like it would work relatively well explained as a type of sound-element magic, although I sincerely doubt that using it would allow "acoustic levitation" or "ultrasonic impact techniques". It would be a matter of forcing magical energy of the wielder's soul to manifest through sheer force of will, making it manifest as one desires... but I already wrote about that in the Compendium Shien showed you. Control of sound could still be rather useful for a lot of purposes, I'd say, despite the awareness of the nature of soundwaves not being understood in Reniam and thus cannot be perfectly reproduced through magic... all the easily detectable properties of sound are known, after all, and those alone should go a long way.
As to the manner in which Claw should "consume the voices" of others, I've been giving that some thought... Draining energy from the environment is probably less applicable in this case, since while this does occur constantly with the entities Shien mentioned, the process is still very slow; in fact a regular mortal would be able to channel as much magical energy from the Spirit Realm in one average night's sleep as a plant would be able to draw from Reniam over two weeks (liches do it somewhat faster than plants, but only if they can continuously relocate to areas with untapped ambient energy; if they stay in the same place they will actually be slower than plants due to having to wait for their surroundings to become resaturated with energy before they can draw from them again). The ability to drain souls is feasible (not very effective if the "defeated foe" is dead, and quite morally questionable if it's alive), particularly if compared to the Xuhrl-njok's ability (which both increases their power and extends their life when they do so), although it doesn't seem entirely fitting in regards to how it's supposed to function in the original concept, with experienced and wise beings possessing more power to consume than beasts as a matter of course (Prophecy wyverns don't roar, by the way; they screech and wail). I started thinking about designing the ability to work by drawing power from others' Seeds of Good and Evil, similar to how Harvesters do (though that would be a [I]seriously[/I] grim comparison to be able to make), but even this doesn't guarantee that things would work the same. But as Shien said it's possible.

And you're right, of course, Shien... the titles are mainly for the players to have a way to get a quick idea of what kind of character it is, and is only secondarily for IC, and even then they are not guaranteed to be used there at all. Aemoten's title as "the Immortal Warrior" is one that is rather unlikely to be known IC, I'll admit, but seemed appropriate for players to quick-reference.
The world... while not officially expanded just yet, as more and more things were added to the south and west in particular (starting when I added the Xuhrl-njok, actually) I started privately filling in the blanks, designing geography and assigning general cultural trends to various areas of the land. It's not as finished as the relevant areas of Kirirak and most of the western nations don't even have names, but all-in-all I've probably mentally expanded the world to some five times the size of the original map. And I think I've ended up deciding on Reniam being a planet after all.

I would post in the IC, but it seems I'll have to wait and see how Morgan reacts to Ixion's spell there, first. And waiting for Ashgan in Jillian's scene...

Oh, and I was just notified that the university I applied to nearly a year ago has accepted the application; I'll be returning to my studies in September.