Xbox Game Pass Standard has expanded its gaming catalog with the addition of Nine Sols, marking the first Standard tier-exclusive title since August 20th. This strategic move comes just one day before the highly anticipated release of Hollow Knight: Silksong, which will only be available on higher subscription tiers at launch.

While Hollow Knight: Silksong continues to generate significant excitement as September 2025's most anticipated Xbox Game Pass release, its day-one availability will be restricted to Xbox Game Pass Ultimate and PC Game Pass subscribers. This tiered release strategy positions Nine Sols as an attractive alternative for Standard tier subscribers seeking a quality metroidvania experience.

The September 3rd addition of Nine Sols to the Standard library offers meaningful value to subscribers. Although not a direct replacement for Silksong, both games share fundamental metroidvania DNA that appeals to similar player preferences. They feature side-scrolling exploration, ability-gated progression systems, hand-drawn visual styles, and challenging "corpse run" mechanics that test players upon death.

The games diverge significantly in combat philosophy. Hollow Knight emphasizes precision platforming and strategic spacing, encouraging experimentation with diverse tools against varied boss encounters. In contrast, Nine Sols implements a Sekiro-inspired parry system that initially presents a steeper learning curve but rewards mastery with satisfying power fantasy elements. Nearly every attack can be parried, allowing skilled players to maintain aggressive playstyles even against formidable bosses.

Nine Sols originally joined Xbox Game Pass in late November 2024, coinciding with its console port releases. While Microsoft typically doesn't disclose specific licensing durations for individual titles, historical patterns suggest games rarely remain available for less than twelve months. This Standard tier expansion represents the second catalog update in September, following the September 2nd addition of I Am Your Beast to all non-Core subscription levels.

The updated Xbox Game Pass lineup for September includes several notable additions across different subscription tiers:

September 4th will also welcome Cataclismo to Xbox Game Pass alongside Hollow Knight: Silksong. The month continues with PAW Patrol World's return on September 10th and the console version of RoadCraft arriving six days later, completing the Wave 1 lineup. The second half of September already confirms Deep Rock Galactic: Survivor and the console port of Frostpunk 2 as additional content offerings.