................................ go for it, bro.

If you are totally sure it's Creative Commons, pass it with MedicineStorm and post it.

Yeah, I guess that's true... but:

1. It's weird and kind of sketchy, and wikipedia does not verify licensing as thoroughly as you may think... or at least not as swiftly as you may think. That being said, yes you should be able to trust the license listed on Wikipedia.
2. The license pertains to copyright, but does grant usage over trademarks. Just because it's CC-BY doesn't mean you're allowed to use any rendition of a trademarked character or trademarked content. It's no different than fan art.
3. See https://opengameart.org/comment/38520#comment-38520

TL;DR: Best not post that kind of stuff to OGA. It could be legal, but still questionable, and hardly received well here. 

It would be pretty funny to use thier content (sans the trademarked stuff). If people are going to twist WMC's open requirement so they can advertise their products, they deserve to have others twist their intent to use the product in competing projects. 

However, the question I was answering was not if it would ok to use that stuff in our own projects. There is a difference between what we are all willing to use in our projects versus what is permitted on OGA. For instance, the new Pixabay license permits anyone to use any of the assets in their own projects, enthusiastically so, but it does not allow redistribution on asset sharing sites. We are legally and ethically allowed to use them in our projects, but OGA is not a game project, it is an asset redistribution site. 

In the same way, I suppose you could use those assets from WB or BroForce legally, but OGA has always had a policy of not hosting art that the artist doesn't wish to be hosted here, even if it is legally permitted for us to do so. This isn't a case of a powerful corporation frightening OGA into obedience despite what the licensing says. This specific scenario has been brought up before (see my link in bullet point #3) and the conclusion was that, legal or not, if it isn't obvious the asset owner wants us to share it, we wont. BroForce was basically saying "well, that wasn't our intent, but I guess it's legal so what can we do?" and Clint Bellanger was very clear that was not sufficient to host it here and was not worth risking bad blood with artists. 

Ultimately, it comes down to this: OGA values the good will of artists more than it values the ability to technically use the assets legally.

I would say in my opinion this case can easily be a "No" on the grounds of trademark ("OGA cannot accept art that contains registered trademarks" from the guidlines). But I agree it's a very interesting case!

I would love to see this get publicity - a quick Google suggests no one seems to have noticed that WB Games may have inadvertedly allowed derivative works for a bunch of their work - but I can see it fair that OGA shouldn't have to be the guinea pig here.

Btw, just to clarify the situation: I don't think the recommendation or requirement to obtain explicit permission to upload (as discussed in link #3, and https://opengameart.org/forumtopic/site-faqsubmission-guidelines-updates... ) did make it into the rules/guidelines, unless I'm missing it? Although if this issue only comes up in a manner that people are unsure on once every 7 years, there is perhaps the argument that it seems fine dealing with it on a case by case basis.

But yes, I know it's always been a rule that authors can request their art be removed (which ended up being the case for the Broforce example anyway).

"Besides this there is a myriad of other proprietary game screenshots/animations/videos like that (e.g. https://commons.wikimedia.org/wiki/File:Broforce_miniboss_animated.gif) from which I can rip their assets and happily upload here."

Or apparently not, as shown by link 3 ;)

As an aside I note that there are also clear examples of sprites ( https://commons.wikimedia.org/wiki/Category:Broforce_sprites ) which does confuse me now, as the discussion in link #3 seemed to focus almost entirely on the screenshots (and the idea that creating derivative works to use in games was unobvious).

@drummyfish - I think it's fine for OGA to choose not to host. I do agree with your comments on free-culture though. On the one hand I think one needs to be careful if someone mistakenly used or misunderstood a licence (and either people want to be nice, or avoid public or legal battles etc). But it isn't unethical IMO to use a work under those four freedoms and according to that licence. The idea of legal-but-not-ethical-to-create-derivative-works would risk polluting free art with content that is legally free but unethical to use. But as I say, I'm still okay with OGA not hosting - indeed, if that's the view of the authors, that's all the more reason not to share it.

I think that the way the rule at https://opengameart.org/content/faq#q-takedown is phrased is very pro-free-culture (it points out the implications of the licence).

I agree: it is always ethical for anyone to reshare anyone's else's work (that is released under a free/libre license) even without asking. I hesitate to say "even against the author's will" because it depends on if the author shared it, then changed their mind vs. the author didn't share it, someone else did... or the "author" shared it but didn't have the authority to do so (derivatives, etc)

"...it doesn't consider the in-depth consequences..."

Such as? I'm not saying there aren't any, but I suspect the consequences are shallower that expected. An author's request to remove legitimately shared art does not halt anyone from continuing to use it. It only halts people from continuing to get it from OGA. It is still listed in every user's download collection (who had already obtained it) and is legally and ethically usable to everyone who aquired it elsewhere or here-but-earlier. It doesn't even halt people from re-sharing the assets as a derivative here on OGA. That rule is not a statement or stance about ethical use of assets, it is a choice made by the admins to promote good will with authors. 

A parable: A young troubled teenaged girl is struggling with the vigors of life. Her parents and teachers, a bit overbearing but well-meaning, send her to a therapist. She hesitates to share how she feels with the therapist, because she has suffered undue consequences for sharing with others before. They all were "acting in her best interest", they worked for the greater good. Their actions weren't bad or wrong neccessarily, but the consequences were never-the-less undesireable to the young woman. 

The therapist assures her that anything she says is kept in confidence and no one else will hear about the conversation. She opens up and shares her feelings of self harm and other dark things. 

The parents and teachers come to the therapist and ask what she talked about. "I can't tell you; it is priveleged information." They insist that the therapist has an obligation to share what was discussed if it could prevent the young woman from harming herself! If they don't know how she feels, how can they help her!? 

The point is not that depression and self-harm is an allegory for open culture. It is this: If authors think we will share their content even when they do not want us to, even if it is the ethical thing to do, they will choose instead never to share with us in the first place out of fear of the undesireable consequences they may face later when it is no longer within their control.

There have been about 20-50 good (and legitimately shared) submissions that were removed at the author's request. This rule has caused the loss of 20-50 good assets.

There have been about 200-500 good (and legitimately shared) submissions that would not otherwise have ever been shared here on OGA, except for this rule. The artists hesitated to share, but when they were told they could request them taken down, they had no reason to balk at phantom fears. They submitted, people loved the art, their fears of misuse were seen to be unfounded, and the authors decided to share even more. This rule has caused the net gain of 150 (200 less 50) to 450 (500 less 50) great assets to be shared openly. This rule pays more than it costs. Figures are estimates based on my 10+ years of administration here, but they are not hyperbole. Again, this is not to convince anyone to change how they feel about open/libre licensing and sharing. I am 100% in agreement with the stance of irrevokable licenses are legal and ethical in perpetuity. This rule is not intended as a philosophy or to be adopted by individuals. It is specific to OGA. It has reason and considerable forethought for its implementation.

Just wanted to clarify that we aren't anti-FLOSS and are aware of the differences between having this rule as a volutary choice vs. any legal adherence to license or ethical quibbles about it.