Blockbusters like 'Call of Duty' are trying to replicate the runaway success of 'Fortnite' - here's why it won't work

There's another strong reason that "Fortnite" is such a massive success: Despite its violent nature, the game depicts cartoon violence.

Sure, you're firing an automatic weapon, but there's no blood. Graphically speaking, "Fortnite" looks more like a colorful cartoon than a gritty, realistic shooter.

Both "Battlefield" and "Call of Duty" pride themselves on hyper-realistic graphics — look no further than this screenshot of "Battlefield 5" for an idea of how hyper-realistic those graphics are:

While clearly still a video game, firing weapons and other depictions of violence in both "Battlefield" and "Call of Duty" are far from cartoonish.

And that violence inherently limits their audience, as many parents won't let their kids play games intended for adults.

The combination of it being free and available on every platform is hugely important in understanding the runaway success of "Fortnite."

If you have a smartphone, a PC, a Mac, an Xbox One, a PlayStation 4, or a Nintendo Switch, you're able to play "Fortnite" right now for zero dollars. That's huge!

In the case of both "Battlefield" and "Call of Duty," they're only available on the Xbox One, PlayStation 4, and PC. Not being on smartphones automatically limits their potential reach — that's hundreds of millions/billions of potential players!

Between "Fortnite" and "PlayerUnknown's Battlegrounds," there are two major, established games in the Battle Royale genre. Each has anywhere from tens of millions to hundreds of millions of players.

That's before we start talking about games like "Knives Out" and "H1Z1," which have far fewer players but still command large audiences.

At this point, with games like "Fortnite" and "PUBG" so deeply entrenched, it's hard to imagine "Call of Duty" or "Battlefield' competing. The tens of millions of people who love "Battlefield and "Call of Duty" buy those games for what they do best: Simple, fast multiplayer (in the case of "CoD") and sprawling, tactical, squad-based multiplayer (in the case of "Battlefield").

It's possible — likely, even! — that "Call of Duty" and "Battlefield" will offer a new spin on the popular Battle Royale concept. It's unlikely that either will reach the astronomical heights set by "Fortnite" and "PUBG."

Which brings us to the final issue: Fans of "Battlefield" are looking for a great new "Battlefield" game, just as fans of "Call of Duty" are looking for a great new "Call of Duty" game. Whether they're looking for their favorite game to add a new Battle Royale mode remains to be seen.

"Fortnite" and "PUBG" didn't have massive, established audiences when they launched, nor did they have massive, established expectations for what they were supposed to be.

In so many words: If "Call of Duty" and "Battlefield" focus too much on Battle Royale, they risk alienating the loyal audience that plays them. If they don't focus enough on Battle Royale, they risk making a shallow copycat mode that no one wants to play.

It's a damned if you/damned if you don't situation.