Left 4 Dead developer Turtle Rock Studios' 4v1 monster-hunting game Evolve has shipped around 2.5 million copies since its release across Xbox One, PlayStation 4, and PC back in February.

20 percent of all Evolve sales were digital, parent publisher Take-Two Interactive said during an earnings call this afternoon. CEO Strauss Zelnick also pointed out that demand for the game's extensive DLC offerings has been strong.

What's more, Zelnick explained that--based on the success of Evolve--the game has become a "key long-term franchise for 2K."

Also during the earnings call, Take-Two president Karl Slatoff said Turtle Rock will continue to support Evolve throughout the year with new characters, modes, and more.

Take-Two purchased Evolve--then known as Metamorphosis--from THQ for $10.89 million during the company's bankruptcy auction in 2013.

Get the full Take-Two earnings report here.