Rovio is celebrating Angry Birds 2’s second anniversary, and the whole clan’s invited. The 2015 sequel isn’t a smash hit like the original from 2009, but the new multiplayer Clan system could bring back players — and improve engagement.

Starting today, players will be able to band together and win rewards. The first Clan Streak Challenge is launching today as well, and each Clan will receive rewards depending on how many points its players earn from completing levels. Rovio plans on more anniversary events between August 4 to August 11, and there will likely be more Clan challenges to get players engaged in the new system.

It’s not the first time Rovio’s tried to make the series more social. In 2013, the racerĀ Angry Birds Go featured local multiplayer mode, where players could face off if they were connected to the same WiFi network. The studio has been trying to bolster the series, which has been losing player interest over the years. Last year, its revenues grew 34 percent to $203 million, mainly due to help fromĀ The Angry Birds Movie.

Though Angry Birds 2 isn’t attracting a ton of new players, it has found success in engaging its existing fanbase, according to market analyst Sensor Tower.

“We estimate that worldwide monthly revenue for Angry Birds 2 has increased by more than 400 percent since Rovio began rolling out new features and events in the game back in Mach 2016,” said Randy Nelson, head of mobile insights at Sensor Tower, in an email with GamesBeat. He added, “It’s viewed as one of mobile gaming’s great monetization success stories.”