Third-person zombie shooter World War Z is selling "way above expectations" on PC thanks to its Epic Games Store exclusivity, developer Saber Interactive has said.

The game passed one million copies sold this week across PC and consoles, and more than a quarter of those sales were on the Epic Games Store. Saber Interactive chief executive Matthew Karch told VentureBeat that the game has sold particularly well on the store outside of the US.

“Overall the US and EU have been equally strong in sales. We have had 70,000 people playing at once across all platforms, with very similar distribution among PC, PS4 and Xbox," he said. "What surprises us is the fact that sales outside of the US on the Epic Store have been so strong, with the US being only one quarter of sales.”

In a separate press release, Karch added: “On the PC specifically, we are performing way above expectations thanks to the support we have received from the Epic Games Store." He did not expand on how exactly the Epic Store had helped the game exceed expectations.

It's another indication that launching on the Epic Games Store rather than Steam is not harming developers' sales figures: last month Epic said that Metro Exodus, another exclusive, sold 2.5 times better on the store than Metro: Last Light did on Steam.

Partly thanks to the sales of World War Z, the Epic Games Store had a "record weekend" last weekend, according to a tweet from Epic Games on Tuesday.

On Wednesday, Epic Games CEO Tim Sweeney said that the store will stop exclusives if Steam changes its revenue split for developers.

Thanks, PCGamesN.