Activision Blizzard's (ATVI) venerable Call of Duty franchise isn't too old to learn some new tricks. On Tuesday, the video game developer announced surprisingly strong first-quarter sales growth, in part because players flocked to many of its core titles as stay-at-home time surged.

Revenue landed at $1.8 billion compared to the company's $1.6 billion forecast. Management credited the new Warzone release, the franchise's first big move into the battle royale genre, for helping lift results. "The launch of Warzone really took the franchise to new highs," executives said in a conference call with investors while revealing 60 million players had engaged with the game since its March 10 launch.

A young couple plays video games together.

Image source: Getty Images.

Warzone is free to play but offers in-game transactions, and that spending helped push profitability far higher for the company. The popularity of the title also lifted other content in the franchise, including the premium installment from 2019, Modern Warfare.

Activision Blizzard took the opportunity to raise its 2020 outlook since surging engagement metrics have continued into the start of the fiscal second quarter.

While warning that major, unpredictable risks remain, including the potential for a sustained unemployment spike and disruptions in the supply chain, executives suggested that the second half of the year could be strong. "There is a potential for overperformance," CFO Dennis Durkin said, "if these risks do not materialize."