Kevin was encountered in 3x03 The Survivors and turned out to be quite powerful a being, a Douwd. Actually, his powers do remind me of a Q, so is he in some way related to them?
4No he's not a Q. He's a Douwd, whatever that is. Although he's powerful, he seems to lack the ability to alter time or restore people to life (for realsies)– ValorumFeb 21, 2015 at 19:27
2@Richard The way he described his annihilating the entire Husnock race (I think he mentioned "by mere thought") made me think their powers are similar. But of course I'm not asking about speculation but pure facts– ZommuterFeb 21, 2015 at 19:35
5The fact that he so clearly regrets his decision, yet seems powerless to affect it strongly suggests that he's not capable of the same sorts of feats as the Q.– ValorumFeb 21, 2015 at 19:42
3scifi.stackexchange.com/questions/21867/… - There are simply too few canon references to make anything more than a guess.– ValorumFeb 21, 2015 at 20:04
1He isn't Q and it's doubtful that he's related to Q as his powers are weaker than the Q (he can do things but not undo them) and his demeanor is unlike the Q (he felt remorse for misusing his abilities). I think the closest he or his race comes to the Q is that they have evolved closer to the Q than Humans but are still several rungs down the evolutionary ladder. Similarly, the Zalkonians from Transfigurations would be evolving along the same generic path (energy beings with certain abilities) but are less evolved than the Duowd and don't (apparently) share a common ancestry.– geewhizFeb 21, 2015 at 20:16
Within the main canon, the answer is a firm don't know. The extent of his powers and his connection (if any) to the Q Continuum are not described in any great detail.
Points against :
He self-describes himself as a Douwd, not a Q. Note that every other Q that we meet self-identifies themselves as being members of the Q Continuum.
He appears to lack the ability to undo his mistake (destroying the Husnak), suggesting that he cannot time-travel.
He appears to lack the ability to create genuine life (something that would be well within the capacity of a Q), relying on merely constructing himself an elaborate illusion on the surface.
He lacks the ability to merely wish away his problem, relying on a mixture of visual trickery (somewhat akin to a large hologram) and psychically assaulting someone who is close to discovering his secret.
You may also wish to note the very significant differences in the descriptions of their powers in the (fully canonical) Star Trek Encyclopedia
Douwd : A little-known civilization of sentient energy beings capable of assuming the appearance of other life-forms. Possessing awesome powers of creation and destruction, the Douwd considered themselves to be immortal beings of disguises and false surroundings. One member of the Douwd assumed a human identity around 2312, named himself Kevin Uxbridge. and settled on planet Delta Rana IV in 2361.
Q. : An immensely powerful extra-dimensional entity. While possessing near-godlike powers. Q also exhibits a childlike petulance and sense of playfulness.
5Awesome powers < Godlike powers.– ValorumFeb 21, 2015 at 20:43
The douwd could very well be the evolutionary ancestors of the Q, it has been introduced several times in star trek the evolution (both sto and st tng) of physical beings to energy beings, so maybe there are also evolutions of energy beings, becoming progressively more powerful. Following this, the Q evolved from physical life like us to a state of lets call it stage 1 pure energy to maybe stage 10 energy being with omnipresent powers. Could be the other way around too, the Q could be the ancestors of the Douwd lol
Another argument could be the evolution to energy is the last possible step in evolution And the doewd and the Q could be the same race, but have different cultural beliefs as to what is acceptable/ moral behavior for beings with this type of power, when the Douwd described his race as
Possessing awesome powers of creation and destruction, the Douwd considered themselves to be immortal beings of disguises and false surroundings
Isnt this what the Q are? Of everything the Q have done almost all can be explained as illusion, especially, the time travel elements, i have not seen one episode where there was real time change caused by the Q. No matter what, time was always back to where it should be at the end of the episode.
So theres no real proof the Q had more powers then the Douwd, or that they could really manipulate time, the Q for certain love to mindfuk lesser life forms and they lie and lie and lie, so the characters in star trek really have no clue as to the extent of the Q actual powers. So most likely in this scenario they are no more powerful than any of the other star trek energy beings Douwd, Organians, Apollo' race, Gorgan's race, Trelane's etc...
Right from the very beginning The first episode of star trek
shows just how powerful the power of illusion can be.
All speculation aside nothing in the official canon indicates the Douwd and the Q are related in any ways except for similar abilities hence the above thoughts :)