Superb free-to-play first-person shooter Tribes: Ascend has seen over one million downloads in the month following launch, Hi-Rez Studios has announced.

That is, 1.2 million downloads since 12th April.

Hi-Rez boss Todd Harris said the popularity of the game was driven by the players recommending the game to each other. Over 110,000 people have joined Tribes via the friend referral system.

"We see the community expanding primarily through positive word of mouth," he said. "Since release we've already recognized seven players who have each individually referred over 500 new people to Tribes: Ascend.

"The game's success allows us to give back to the community through free DLC updates, tournament events and expansion into new markets in coming months."

Meanwhile, Hi-Rez announced a 31st May release date for the closed beta of its MOBA effort, Smite. To register for the beta, head to the official Smite website. Pre-ordering the game guarantees access.