So how precisely does Wiki Wars work?
Basically, all the players are given five random wiki articles, (At first they focused entirely on wikipedia, but then sub-wikis[stuff like TVTropes, Gamepedias, and various Wikias] became a bigger focus) and those articles are used to decide things such as the players items, allied NPCs, bonuses, and abilities.
This game is also using the avatar system which has been used twice before, where your first article is used to decide what/who you are playing as, and is one of the biggest contributors in terms of equipment and abilities.
A lot of actions are decided based on the result of a d10 being rolled, when making an attack against someone else the difference between the two rolls(the attackers and their targets) is used to decide how effective or ineffective the attack is, if the attackers roll is
too much lower than the defenders than the defender can make a free counter attack.
This game seems to be using a system similar to random Wikia War where the wikis are chosen from a big, visible list rather than just being mysteriously decided upon. Though this game is taking active suggestions for wikis to pull from where as Wikia War has adding a new wiki to the list as the winners reward.
Speaking of the wiki list
0cra, here's some suggestions
The SCP Foundation: It's basically one big wiki, even being labeled as such in the URL. It even comes with a random SCP button right on the front page to give you a random article(because a good number of the pages are stuff like short stories instead), though there's things such as the GoIs that you might want to look into as well for your searching. Regardless, you'll definitely get some unique results out of this one.
Official Enter the Gungeon Wiki: This will give you a nice supply of simple stuff, as well as some silly, and some particularly powerful. A good wiki for getting lots of creatures, weapons, abilities and items.
Mario Wiki: I'm honestly not sure there's a wiki out there with more articles. There probably is, but still, this one will provide you with a
massive amount of different articles, and I guarantee you will be able to use a large majority of them.