Developer ZeniMax Online Studios has announced a new Loyalty Program for its massively multiplayer role-playing game The Elder Scrolls Online.

Starting in September, players who have paid the game's subscription fee for three months, excluding the free game time included with a purchase of ESO, will receive a High Hrothgar Wraith vanity pet that they can parade around Tamriel. ZeniMax said that it will soon reveal the next reward, given to players who've been subscribed for six months. If you haven't been subscribed for the required period of time, you'll still be able to get the rewards once you've met the requirements. ZeniMax added that the loyalty program will continue to expand over time.

In its latest Road Ahead update, ZeniMax also shared some details about additions coming in Update 4. It will feature the final region of Craglorn that will complete the story of the the first Adventure Zone, and the Serpent Trial, the final Trial in the constellation storyline. Like the original Trials, it's designed for a group of 12 players. Finally, the last major content addition in Update 4 is the Fragonstar Arena, a PvE event where a group of four players will face progressively more difficult waves of enemies to earn prizes.

According to a recent report from SuperData Research, World of Warcraft earned more revenue than any other subscription-based MMO in the world during 2013. ESO, not surprisingly, hasn't been around long enough to crack the top 10. Traditionally, subscription-based MMOs lose a portion of their user base after the initial month when people decide not to renew their subscriptions. ESO, though, has held on to 772,374 of its subscribers as of June, according to SuperData.

The Elder Scrolls Online was released on PC in April and earned a 6.0 in GameSpot's review. It was supposed hit PlayStation 4 and Xbox One in June, but has since been delayed.

What incentive will convince you to pay a monthly subscription fee? Let us know in the comments below.