Venipuncture is one of the most common invasive procedures in children and is often associated with significant pain, fear, and anxiety.This randomized controlled study will aim to evaluate the effects of a video game-based breathing exercise intervention on pain, fear, and anxiety levels in children aged 7-12 years undergoing routine venipuncture. While the intervention group will receive a video game-based breathing exercise using the BREATHING+ system in addition to standard care, the control group will receive routine venipuncture procedures only. The study population will consist of children aged 7-12 years who meet the inclusion criteria and whose parents/legal guardians provide informed consent. Participants will be randomly assigned to intervention and control groups. Pain, fear, and anxiety levels will be assessed at three time points: before the procedure, during the procedure, and immediately after the procedure. Data will be collected using the Visual Analog Scale (VAS), Children's Anxiety Scale-State (CAS-S), and Children's Fear Scale (CFS), along with a structured questionnaire form. All assessments will be conducted at the predefined time points.