Looking at it, it's a Digifuse instead, from one of the Virtual Pets. But yeah, like I said, it's not common in the anime either.
The games and manga don't always follow that either way. Which makes sense, as there's often no reason to. Very specific DNA's are story-based, not simply just an option, so a good story justifies them, etc as I said before.
Also, DinoBeemon is another neat one who is the opposite of Paildramon. Interestingly enough the opposing DNA also exists for the 02 characters. Angemon can use Ankylomon to go into MagnaAngemon(which is an armored angel still), and Angewomon comes from Gatomon and Aquilamon(which in this case, is an angel with feathers, soooooo).
Yeah, if you only watch the anime, you'll see a pretty nice route for the DNA's. I like how proper they are, as they feel like natural combinations. Digifuses later work the same way in the anime. Do note that in the games, Digifuses basically are often just another DNA for all intents and purposes, so same rules apply. All 4 Dark Masters can become Apocalymon, for instance. Just like DNA'ing two members of the Dark Masters would(though it depends which combination of Dark Masters as well). It's probably just their way to push the gimmick more and more, by making it "hey, it's just DNA again".
