Ok so since you asked, what is a mutant vehicle? We start with the premise that all vehicle traffic on the playa has a significant negative impact on the event in terms of stuff like dust, pollution, traffic, safety, etc.
Thus, we define a mutant vehicle as a vehicle whose contribution to the event exceeds its negative impact.
That's obviously more than a bit vague, but it does give us the flexibility to license stuff that just has to be licensed because it's so awesome.
Typically, tho' what we are dealing with is aesthetics - what does the vehicle look like? This easily accounts for 99% of MVs we handle every year. And we try an adopt an "average burner" viewpoint. Would the "average burner" think this vehicle improves the event? This is obviously still vague, as what's an "average burner". So what we've done is really taken the word "mutant" to heart.
What we're looking for is a vehicle that have been mutated into something other than the base vehicle.
Does the vehicle look more like Toyota pickup or a dragon, or cat or boat or whatever? The more it looks like a dragon and the less it looks like a pickup, the more likely it is to be licensed. And, honestly, for me, it's really that first glance that counts most. Further, we look at how well executed the mutation is. Sloppiness doesn't get you any points.
And we specifically don't license what we call "decorated, not mutated". Which is what happens when someone glues fake fur and zip ties doodads to their golf cart.
Oh, and another thing a mutant vehicle isn't is subtle. If you have to explain what's going on, it probably isn't a mutant vehicle. A classic MV should be identifiable from halfway across the playa...in a dust storm.
With night licenses, the same basic rules apply. There has to be something interesting to look at. This is usually accomplished with some sort of light or flame effect or simply illuminating vehicle so that you can see why it qualified for a day license.
One thing we try avoid, to the best of our human abilities, is judging the artistic merit of a vehicle's mutation. At the DMV, bad art is still art.
I hope that answers your question.
Does this mean that you'll never see another fur-covered golf cart on the playa? No, but those vehicles did NOT go through the Mutant Vehicle licensing process. Disabled participants, while encouraged to decorate their vehicles as best they can, are not required to do so for their license. Art-support vehicles are licensed through the Artery, and not subject to the Mutant Vehicle criteria. And the staff golf carts? Those are all rentals, and by the time the staffers who are using them actually take possession, they're too blasted busy WORKING to decorate them, for the most part.