The number of people playing World of Warcraft has dropped by 1.3 million in the space of three months, a 13.5 percent decline. Activision says the growth of free online games has hurt, but has promised to release new content more frequently.

The figures cover the first quarter of the year. According to the company’s CEO Bobby Kotick, further declines are likely and he fully expects to finish 2013 with fewer players than at the start of the year. However, he says the game remains highly successful (eight million subscribers still remain) and indicated Activision remains fully committed to it.

The company said most of the decline in players came from Asia. That’s despite specific attempts to appeal to that market such as the release last year of the Mists of Pandaria expansion pack.

Kotick said that “It’s important to note that the nature of online games has changed, and with the environment becoming far more competitive, especially with free-to-play games.”

It seems Activision and WoW developer Blizzard have a two-step plan for trying to slow the decline. Firstly it plans more frequent content updates so that existing players stick around longer.

Secondly, it will look at ways to make it more enticing and less hassle for lapsed players to return. Blizzard CEO Mike Morhaime didn’t give any specifics but talked about the need to “adjust our approach to player behavior and preferences.”