A major game publisher is closing studios and killing 6 titles—here’s why

One of the giants of the gaming business has tumbled off a cliff.

Ubisoft, the French game publisher best known for the Assassin’s Creed series, just announced plans to dramatically reorganize its business. In the process, the company will kill six games it had in the works, including a long-awaited Prince of Persia title that was expected this month. Ubisoft shares dropped by more than 30% following the news.

The game publisher said the changes are designed to make it more...