K2 Horizon comprises a network of six open models, including the 375B-A23B, 36B-A4B, 32B, 7B, 3.7B, and 0.9B, all engineered to excel in various domains such as reasoning, mathematics, coding, agentic tasks, and overall capabilities. These models share a unified architecture, vocabulary, training techniques, interfaces, evaluation frameworks, and deployment tools, facilitating seamless transitions between sizes and dynamic workload management. The fleet's flagship, the 375B-A23B model, is particularly adept at handling intricate reasoning, software development, research projects, and long-term agentic functions, while the 32B and 36B-A4B models focus on delivering robust local deployment solutions. Notably, the 36B-A4B model features an innovative Mixture-of-Value Attention mechanism, which merges sparse attention with Mixture-of-Experts layers, allowing it to engage approximately 4 billion parameters per token and compete closely with the performance of the denser 32B model. This architecture not only enhances flexibility but also maximizes resource efficiency across a wide range of applications.