Backdoors & Breaches is a cooperative incident response card game designed for security training and tabletop exercises. The Core Deck contains 52 cards representing Attacks, Detections, and Injects that teams use to simulate realistic incident response scenarios. The game uses a structured framework where an Incident Captain creates attack scenarios using four categories of Attack cards: Initial Compromise, Pivot & Escalate, Persistence, and C2 & Exfil. Defenders work cooperatively to uncover the attack path within 10 turns using Procedure cards, dice rolls (d20), and critical thinking. Each card includes descriptions, detection ideas, tools, and resources for continued learning. The game supports 5-7 Defenders plus one Incident Captain, though it can be played with as few as two players. Sessions typically run 30-60 minutes. The product includes downloadable resources such as a Visual Guide for setup and gameplay instructions, and a Turn Tracker for recording findings during exercises. An online version is available for virtual gameplay. Organizations use Backdoors & Breaches to train incident response and blue teams, run structured tabletop exercises, introduce new analysts to IR concepts, and facilitate discussions about detection coverage, tools, and playbooks. The game is used by educational institutions, security consultants, enterprises, and government teams.