The micropatch 15.1b for League of Legends introduced significant changes in champion balance, system mechanics, and, importantly, nerfs to the new upgraded boots and one of the new mechanics.

Summoner's Rift

System nerfs in patch 15.1b weakened several key game mechanics and items, including various types of boots that significantly affected match outcomes.

Quick Game 

Adjustments also impacted the Quick Game mode, where some game elements and champion balance were revised.

Champion Changes

System Changes

• Atakhan Form Frequency

Boot Nerfs and Their Impact on the Meta

The analytics portal DPM.LOL conducted a statistical analysis, revealing that the win rate of teams on the blue side using boots with "Triumph of Power" reached 71.4%, significantly exceeding the 69.9% of teams on the red side. 

These imbalances necessitated changes in patch 15.1b. After the update 25.S1.1, the boots were too powerful, leading developers to decide to reduce their effectiveness. The nerf started in patch 15.1b, with further reductions planned in the next update to improve balance and increase strategy diversity.