A 13-year-old boy learned a valuable lesson after his “Fortnite” account was hacked and his expensive avatar was killed off by a stranger during a gaming session last week.

Jake Bates, of Mason, Ohio, was in an intense battle with another gamer, discussing the action on a headset, when the player volunteered to transfer over cool new designs if he gave him access to his account.

Bates, eager to get free items to improve his video game character, agreed — and told the unidentified player his username and password.

“When he logged into his account, he took everything over,” Bates’s mother, Amy, told WLWT. “The guy took over his account, but also took over his email account and changed the passwords, changed the recovery passwords and the phone number.”

The teen suddenly realized he was in trouble. The stranger now had access to his personal information, including his mom’s credit card number. And even more devastating for the “Fortnite” enthusiast, the scammer killed a character Bates spent “hundreds” of dollars on, according to WLWT.

“It’s really scary,” Amy told the news station, adding that her son “feels violated” by the stranger’s act.

Amy said “Fortnite” warns players not to share personal information and urges those who witness bad behavior to report it immediately.

Epic Games, the developer of the hit game, has not yet returned Fox News’ request for comment.

Epic Games’ free “Fortnite Battle Royale” spin-off is wildly popular, becoming the most viewed game on YouTube earlier this year — surpassing “Minecraft,” “PUBG” and “Clash Royale,” according to data released in March by influencer marketing platform Matchmade.

“Fortnite,” described as a cross between Minecraft and a shooter-survival game, allows players to fight other players, enemies and build shelters while navigating a vast landscape.