Russians are apparently not the sort of people to let a little copyright infringement get in the way of a good story.
With so many extraordinary characters appearing in the games, movies, comics and TV shows that gamers and geeks love so much, there's plenty of scope to ask questions like "What would happen if Superman fought the Hulk?" or "What's faster, the Starship Enterprise or the Battlestar Galactica?" As far as I know, no one was asking "What would happen if the Teenage Mutant Ninja Turtles met one of the aliens from Predator?" but a series of Russian children's books has kindly gone and answered the question for us anyway.
We've only got the wonderfully ugly pictures to go on, but it seems that the initial contact between the Turtles and the "Space Hunter" as he is referred to, goes badly, and ends in fisticuffs. They soon resolve their differences however, after the Turtles rescue the Space Hunter from a prison of some kind - possibly belonging to the Shredder, although he doesn't seem to appear in the book. After they make their escape, they go and get a bite to eat while April conducts an interview with Donatello. Don't ask me why, because I have no idea. As for Batman, the Turtles actually team up with him fairly often, fighting against militant groups, the Mafia, and even a wizard. In fact, the gang spend so much time together that Batman has the chance to put his bat-moves on the Turtles' human friend April O'Neil after getting wounded fighting some mobsters.
There are more than thirty books in total, each one an ugly, strange flower that has to be seen to be believed. You can see the whole range here and maybe, if you've got a few minutes spare, you can try and figure out what on earth is going on.