Integrating Mixed Reality (MR) into nursing education and professional practice has recently captured significant interest as a transformative approach. This paper presents a comprehensive exploration and practical insights into designing and implementing an advanced MR training platform to provide nursing students with immersive experiences across various patient care scenarios. Further enhancing the platform's utility is the incorporation of a unique conversational artificial intelligence (AI) module. This innovation breathes life into digital patients, enabling dynamic and realistic interactions that challenge nursing students to develop clinical reasoning skills in a controlled yet flexible MR environment. The AI's capacity to understand and contextually react to the learner's' verbal and behavioral inputs simulates authentic patient interactions. A total of 7 nursing students and 3 nursing faculty engaged in the pilot study, which served as a proving ground for the MR training system's effectiveness. The study involved in-depth analysis, employing performance metrics, and evaluating situational awareness alongside cognitive workload using NASA Task Load Index (TLX) and learner's thought verbalizations. The primary objective was to create a system that enhances nursing students' competencies and readiness for clinical healthcare practice. This system can potentially elevate the preparedness of new graduate nurses by providing a rich, interactive learning environment that mirrors the complexity of real-life clinical settings.