Lifeblood Gear

As an action, you can attach this tiny bronze gear to a pile of junk or other small collection of mundane objects and create a Tiny or Small mechanical servant. This servant uses the statistics of a beast with a challenge rating of 1/4 or lower, except it has immunity to poison damage and the poisoned condition, and it can't be charmed or become exhausted. If it participates in combat, the servant lasts for up to 5 rounds or until destroyed. If commanded to perform mundane tasks, such as fetching items, cleaning, or other similar task, it lasts for up to 5 hours or until destroyed. Once affixed to the servant, the gear pulsates like a beating heart. If the gear is removed, you lose control of the servant, which then attacks indiscriminately for up to 5 rounds or until destroyed. Once the duration expires or the servant is destroyed, the gear becomes a nonmagical gear.