A 45-year-old California man pleaded guilty in federal court Thursday to ripping off $4.8 million from his employer. Notably, the man admitted to spending $1 million of that bonanza on Game of War.

The mobile-phone game is developed by Machine Zone and heavily advertised by model Kate Upton. It's one of the top-grossing mobile games in the world, according to Adweek. And now we know why, at least in part.

Kevin Lee Co admitted in Sacramento federal court that,from May 2008 to March 2015, he embezzled nearly $5 million from his controller job at a heavy-equipment company called Holt California. He admitted in his guilty plea (PDF) to spending "approximately $1 million" on Game of War. He also admitted to getting plastic surgery and buying season tickets to the San Francisco 49ers and the Sacramento Kings. The record also showed Co bought "luxury cars" and a golf club membership.

We've read reports about players spending thousands of dollars on Game of War, which bills itself as "the world's largest multiplayer strategy game." It's raking in more than $1 million daily, but we've never seen a personal tab this high to date.

The strategy game sees players building empires with soldiers and attacking other players who are doing the same. The deeper you go, the more likely you'll shell out cash. VentureBeat said that Game of War's paying players spent an average of $550 on the game last year:

A $550 annual average is insane, but Machine Zone has definitely mastered certain aspects of getting people with a lot of money to part with huge chunks of it. A big part of this, as analytics firm ThinkGaming points out, is that Game of War has a lot of depth for big spenders. The app has a multitude of systems that players need to engage with to ensure they have an army prepared for the next big multiplayer battle. But those systems are slow, and players can speed them up by spending cash. Of course, a lot of games do stuff like this, and part of Machine Zone’s success is that other studios haven’t figured out how to duplicate its money-making techniques. It’s also likely that Game of War has a disproportionate number of whales compared to those people who put just a few dollars in. The game heavily favors big spenders, and the top whales are a hundredfold more powerful than the common player who puts little or no cash into Game of War.

Cracked, meanwhile, did a piece last year entitled "5 Reasons I lost $9,000 On An iPhone Game." One reason is that players don't get to keep what they buy in Game of War.

"But, here, you're spending money on troops and other expendables that can be lost in combat. I was casually browsing the map at work recently and came across a guy who must have spent at least 7,000 Euros. He wasn't around to defend himself, so we attacked. We wiped out about 2,500 Euros. Two-and-a-half grand, gone in five minutes," according to Cracked. "It's like gambling, but with no possibility of winning."

For Co, the convicted embezzler, money was no object with Games of War. After all, he was gambling with his employer's money in additional ways. Co now faces a maximum 20-year term when sentenced in May.

Listing image by Machine Zone