I had a feeling this was gonna be done at some point and boy it's gonna be a hassle. I'll do this like I've done previous threads that aren't created by me and that is listing categories and who has the advantage in which regard.
Attack Potency/Durability
From what I can see, Ben's 6-B Aliens are back scaling from there High 6-B selves who scale from this feat from
https://vsbattles.fandom.com/wiki/Vilgax. Meanwhile 6-B Danny Phantom is around baseline at minimum for being at least twice as strong as Vortex who
did this feat.
Given the Ben 10 Aliens are in the upper border of 6-B as signified by the "+" next to their Attack Potency, I'll say Ben's 6-B Aliens can smack Danny around in terms of AP. Now while Danny can amplify his physical strength with ectoplasmic energy and has Reactive Power Level which can easily allow him to tare apart people on his level or who were stomping him, the gap is unknown.
So Ben's Aliens have a good advantage in terms of power.
Speed
Speed is Equalized so this doesn't matter as far as I'm concerned.
Intelligence/Experience/Skill
I haven't watched the later Ben 10 series apart from some episodes of each but that was years ago so I can't really go into detail on how smart Ben is but I can say he's obviously adapt enough in combat due to his various battles with different aliens and capable of using his aliens abilities well when needed. There are aliens that make Ben extremely intelligent beyond reason such as
Gray Matter and
Brainstorm.
Danny's similar to normal Ben's intelligence as he's combat a verity of enemies that while all were ghosts, each had a unique ability and personality so they didn't all fight the same and he's even managed to outsmart Gifted and Extraordinary Genius like Skulker and Vlad Plasmius at times. He's well adapt at using his powers when the situation calls for it so he isn't a complete fool.
So in the end I'm gonna give intelligence to Ben but only when using aliens like Gray Matter and Brainstorm, other than that I wouldn't say either is far smarter than the other in terms of combat skill in there own regards.
Stamina
Many of Ben's aliens have High or Unknown stamina ratings with little to no justifications for the ones with High so there isn't much I can say, obviously they don't all have trash stamina and can fight for awhile but without context I can't say for how long.
Danny on the other hand was able to fight and chase ghosts for 24 hours straight and held his ghost form and invisibility while spreading it over an entire jet for hours as well as go on a 3 day trip with little food and rest. While the Ecto-Skeleton does drain Danny's energy in order to power itself, it's only an issue when he uses to much to fast. We've even seen the suits energy supply go back up when he's not doing anything.
So I'd say Danny can outlast Ben so long as he doesn't push himself beyond his normal capabilities which is unlikely to happen since he already knows he has to manage the amount of power he uses.
Range/Area of Effect
Took me a minute to look at all of Ben's Aliens range section. Most don't have much in terms of range with the exception of aliens like
Big Chill who made it snow in the Null Void (but his range is only Tens of Meters?....) or
Feedback who has hundreds of meters with energy attacks and maybe a few others but I'm not sure which and I don't know if there range needs to be updated or not.
In Danny's case, his energy attacks are at least hundreds of meters and should be comparable to other ghosts on his level who's energy can reach across Amity Park (City). While in the Ecto-Skeleton we've seen Danny's energy beams gain a massive boost in area of effect to the point were he could nuke over a hundred of Pariah's Soldiers with a single blast.
While I do believe some of Ben's aliens do have higher range then Danny, majority of his aliens do not so I wouldn't say either have a massive advantage but if Danny does decide to play the range game, most of Ben's aliens will be at a massive disadvantage especially since Danny can and does fly a lot which not all of Ben's aliens can do.
Versatility/Abilities
This is a blatant example of "Quantity vs Quality". I'm not about to spend all my time going over each alien but there are some that I think are notable enough that deserve being mentioned and how they can contribute to Ben in this fight.
Feedback: His energy absorption will allow him to absorb Danny's ranged attacks which will limit Danny to fighting him up close and since Danny's attacks can also hit ghosts like him, Feedback has a way to counter Danny's intangibility.
Ghostfreak and Big Chill: I believe they might the right intangibility needed to interact with Danny while he's also intangible so he's definitely worth mentioning as it gives been the means combating intangibility
Brainstorm and Gray Matter: While their abilities aren't really not worthy, their intelligence is valuable. The Ecto-Skeleton may be ectoplasm infused while Danny is inside it, it's still technology and there isn't a doubt in my mind either of them can't hack or take apart the Ecto-Skeleton which is what makes Danny 6-B in the first place.
Toepick: His fear hax is not based on mental stuff so this alien should be a solid way for Ben to incapacitate Danny via fear.
Wildmutt: Wildmutt isn't much but his high sense of smell would allow him to track Danny while he's invisible.
Echo Echo: Duplication would help if Danny duplicated as well and his sonic scream can pose a danger to Danny for sure.
Clockwork: His time powers are definitely helpful but I don't recall if he needs to turn the dial on his head to activate them, if so than it's gonna be hard to get them off.
Diamondhead and Cannonbolt: These guys can reflect energy attacks so this is a good counter for Danny's ranged attacks.
There are obviously more aliens in Ben's arsenal that I think can provide support but I don't have the time to look at all of them and the one one's listed above are the one's I think are notable enough that they could be mentioned.
Danny has a decent amount of things going for him in terms of quality. His regeneration already allows him to handle anything most of Ben's aliens can due to him, his invisibility and intangibility are also hard counters for many of Ben's aliens as they have no way of seeing or touching him.
His ectoplasmic energy attacks can effect the body on a molecular level and vaporize, plus phasing can also be used to ignore conventional durability against the organic aliens that can't regenerate. Duplication is also something not all of Ben's aliens can combat.
Body Control is also something that can help Danny avoid attacks against those who can harm him while he's intangibile and while his shields may not be able to stand up against the power behind majority of Ben's aliens, it's attack reflection properties can keep him safe against his own attacks if thrown at him.
Supporting things such as blinding some of Ben's aliens with flashes of light or attacking from underground while intangible are also helpful. There is more I'd like to say but I'm tired and I don't want this comment to go on forever so I'll add two notes then move on to who I'm voting for.
Important Note: Me and Greenshifter already had a debate about wether or not Ben resists Danny's type of possession and the answer was yes so I won't be discussing that.
Important Note 2: I did not include Danny's Ice Manipulation or Sonic Scream because he did not possess them when he had the Ecto-Skeleton which was early season 2 in debut.
My Vote
I'm gonna vote for Ben Tennyson...
With speed being equalized, Danny cannot blitz and majority of Ben's aliens are much stronger, some to an even higher degree. AP isn't everything obviously considering some aliens are still weak in terms of physical stats and majority of them lack the means to actually harm Danny do to his physiology and regeneration or even touch him thanks to intangibility.
However Ben is not completely at a lose as despite majority of his aliens lacking the right Non-Physical Interaction, they can tank any physical attack Danny throws at them do to there higher durability. It won't be impossible for them to dodge his energy attacks either as Danny won't apply the massive area of effect unless he's up against a horde of enemies so unless Ben turns into Ditto which is a stupid move, Danny wouldn't likely do it.
Also, Ben still has aliens like Big Chill and Ghostfreak who I'm giving the benefit of the doubt can effect him when he's using his intangibility. While Ben himself isn't vastly smarter than Danny, the likes of Brainstorm and Gray Matter are and should easily be smart enough to mess with the Ecto-Skeleton if they get a chance.
Toepick is an easy win for Ben considering it's not mind based so Danny can't resist it. Echo Echo can duplicate himself to even the odds if Danny does as well and his sonic scream could mess Danny up in regards to his hearing. Clockwork's time powers can also be a problem if he gets them off and as I pointed out above, aliens like Diamondhead and Cannonbolt bolt can reflect energy attacks, not to mention Feedback who can absorb and shot it back.
Another important thing to note is that Ben's watch would turn him into the best alien needed to survive against what Danny is doing so even if Ben chooses Four Arms or something useless it wouldn't remain out for long. I think Danny could phase the watch off of Ben's wrist but that's only if he catches Ben in human form after he sees him utilizing the watch to transform which is not likely given Ben has master control.
Danny's immense stamina could be an issue and he might be able to outlast Ben if he plays it smart but Danny would be surprised by Ben's abilities in some regards and if he feels he needs to he would start wasting more energy which would cost him his stamina. Flight is also an advantage as many of Ben's aliens lack the range to hit Danny from far away but this would also limit Danny's attack choices as well. The fact that Ben also resists Danny's Possession is a problem.
All in all, I feel that despite Danny's abilities Ben also has win conditions that are more likely to happen due to the watch switching him to a good alien if he chooses a crappy one. Danny also isn't gonna go full area of effect right of the bat either.
Again, I know I didn't go over ever alien in Ben's arsenal but I feel that it would be pointless since some are basically useless and won't be any help against someone with Danny's abilities. Pesky Dust's Sleep Manipulation would likely work but Danny's covered by the Ecto-Skeleton which id sealed so the dust wouldn't get in, Gutrot has gas abilities but unless they work on non biological beings I don't think he's useful, Gravattack has Gravity Manipulation but ghosts are resistant to gravity so he isn't gonna due much so you can get the idea of what I'm saying.
Regardless, I'll vote Ben. I think the fight is a good concept and really utilizes the "Quantity vs Quality" in a good way. Now I'm going to bed.
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