As long as I don't sell/make money off of my game, and credit is given, am I allowed to make a game that involves other people's copyrighted characters and post it on Quest? I love reading and writing fanfiction, and Quest would be perfect to make the type of fanfiction I like interactive.

(Replying to my own post aaaa) I searched "fangame" and found some results on Quest, so I guess it's okay

you can't use someone else's (intellectual for this subject/topic) property...

(well, you can... until you or quest site gets a cease and desist letter from the property owner's lawyer... as now there's a very negative consequence for continuing to unlawfully steal/use someone's property)

you need to read up on copyright and/or patent and/or trademark laws... or just understand that there's almost no allowance... despite whatever false notions you have that something is "okay/lawful" to do, as it's NOT "okay/lawful", it's UN-lawful.

here's the US' copyright law:

https://www.copyright.gov/title17/

not a business lawyer (though I took a business law 101 class), but this looks like it might be relevant for understanding the law:

https://www.copyright.gov/title17/92chap13.html

there's many more sites you can look up this stuff for more friendly (layman / non-business lawyers) resources, but you need to make sure the site's information is legit

here's a somewhat more understandable resource:

http://info.legalzoom.com/legal-use-disney-characters-21231.html

(google searching for 'disney copyright cases', is a good way to find the cases/laws on copyright/trademark/patent)

also, this is a good read too (arnold swartzeneggar vs bobblehead arnold swarzeneggar):

(the article doesn't explain that arnold being rich, has a very powerful/successsful and thus aggresive lawyer / legion-firm of laywers, which scared the $#@#@ out of the defendant party, hence the "settlement"... entirely in arnold's favor... the defendant party got "pwned", it wasn't a "settlement" for them, it was for arnold)

http://digitalcommons.law.scu.edu/facpubs/79/

here's the article's portion telling that the "settlement" was entirely in arnold's favor (they got pwned by arnold's lawyer/s):

(if you want to read more about the legal proceedings, start at the 'The Dispute' section of it, otherwise, you can read the entire thing, the background about both parties)

According to the Press Release: 
The parties have agreed that all Schwarzenegger dolls 
holding a gun will be permanently discontinued. ODM 
will be permitted to manufacture a new doll of Governor 
Schwarzenegger, without a gun, approved by Oak .... 
The parties have agreed that a substantial portion of all 
sales of both dolls (with and without a gun), will be do­ 
nated to Schwarzenegger's charity, Arnold's All Stars. In 
addition, the Bosleys have agreed to donate a portion of 
Schwarzenegger doll sales to a charity oftheir choosing. 57

You've also got to consider the moral implications - even if no one seems bothered you've used their characters/ideas.

Best thing to do in these situations is put yourself in their place and ask how you'd feel if you found a game/story/artwork that was using your copyrighted material and you weren't even consulted over their use.

Having said all that, 'fan' based stuff does seem to be largely accepted, even by the original creators/owners, and is usually seen as 'flattery'.

It all depends how you go about it. I heard rumours that JK Rowling kicked up a bit of a fuss when people started churning out fan-based Harry Potter stuff, so you never know.

Actually JK Rowling has given blanket permission for people to create fan fiction based on the Harry Potter world (as long as they do not make money from it).

Oh, I see. I knew I'd read something about her and fan fiction.