How Aggro Crab and Landfall Conquered the World With the Co-Op Climbing Game PEAK

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GameDiscoverCo brings us some fascinating insights into how PEAK took the gaming world by storm. This co-op climbing adventure, developed by Aggro Crab and Landfall, has sold 4.5 million copies since its release on June 16, 2025, on Steam. Priced at just 7.50 €, PEAK exceeded all expectations, reaching 100,000 daily concurrent players and surpassing the success of the studios’ previous titles, such as Another Crab’s Treasure.

Development of PEAK began as an experiment meant to help Aggro Crab recover from burnout after three years of working on Another Crab’s Treasure, a soulslike game that sold between 600,000 and 700,000 copies. Nick Kaman, head of Aggro Crab, revealed that the idea came from a sense of “jealousy” toward Landfall’s Content Warning, which found huge success after just a month of development.

In February 2025, three members of Aggro Crab and four from Landfall gathered in Seoul, where they spent a month working intensively in an Airbnb in the Hongdae district. Although the concept was initially sketched a year earlier in a Swedish jacuzzi, it evolved into a precise vision for a co-op climbing game with survival and comedic elements.

Unlike typical game jams, PEAK had a clear goal: create a commercially successful game in a short time frame. The teams leveraged Landfall’s technical expertise in online co-op multiplayer and ragdoll physics, enabling rapid development. The game revolves around a simple but brilliant mechanic — managing the stamina bar. This bar depletes while climbing and replenishes during rest, shaping every aspect of gameplay, from navigating dangerous terrain to handling injuries and resources. Additional factors like backpack weight or poisoning also affect stamina.

PEAK stands out for its cooperative nature, allowing up to four players to climb a mountain that changes every 24 hours. You must work together, help each other across cliffs, and share ropes and equipment such as pitons. Moreover, its procedurally generated map and comedic slapstick moments make it highly watchable on platforms like YouTube, Twitch, and TikTok.

Kaman revealed that, following Valve’s advice, they avoided a free-to-play model because many games that attempted to replicate Content Warning’s success failed. Promotion was minimal: the first trailer dropped only four days before launch, and the Steam page accumulated 29,384 wishlists before release. Instead of a planned marketing campaign, success arrived organically through viral social-media moments.

The numbers speak for themselves: PEAK sold one million copies in its first six days, two million in nine days, and 4.5 million by early July, with 93% positive reviews out of 37,081 on Steam. The game hit a peak of 102,799 concurrent players and currently maintains around 100,000 daily players, placing it among Steam’s top sellers.