Saber Interactive's zombie shooter World War Z has surpassed 1 million sales in its first week on shelves. 

The co-op title launched on April 16 for PlayStation 4, Xbox One, and Windows PC, and notably skipped Steam in favor of Epic Games Store exclusivity. 

Speaking to VentureBeat, studio co-founder Matthew Karch explained the game did better than expected outside of the U.S., and has so far managed to attract 70,000 concurrent players.

“Overall the U.S. 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 (Epic Games Store), PS4 and Xbox One," commented Karch.

"What surprises us is the fact that sales outside of the U.S. on the Epic Store have been so strong, with the U.S. being only one quarter of sales."