Might of the Master. The following numbers increase by 1 when your proficiency bonus increases by 1: the Defender’s skill and saving throw bonuses (above), the bonuses to hit and damage of its rend attack, and the number of hit points restored by its Repair action (below).

Versatile. The modular defender has two modes : Mobile and Integrated.

Mobile Defender. In this mode, the defender shares your initiative count, but it takes its turn immediately after yours. It can move and use its reaction on its own, but the only action it takes on its turn is the Dodge action, unless you take a bonus action on your turn to command it to take one of the actions in its stat block or the Dash, Disengage, Help, Hide, or Search action.

Integrated Defender. In this mode, the defender attaches itself to specialized facets of the Battle Smith's armor. It still shares your initiative count, takes its turn immediately after yours, but it cannot move and occupies the same space as you.

While integrated, the Battle Smith's speed is increased by 5 ft. and they can activate Coordinated Defense, using a bonus action. You can also take a bonus action on your turn to command it to take one of the other actions in its stat block or the Help or Search actions.

Vigilant. The defender can’t be surprised. When interfaced with the Battle Smith's armor, they share this trait, but have disadvantage on initiative rolls.

Environmental Scanners. When integrated, Passive Perception checks are made using the higher of the two scores. The Battle Smith also gains limited Darkvision (30 Ft.) if they do not already have it.

Constructed Nature. If the mending spell is cast on it, it regains 2d6 hit points. If it has died within the last hour, you can use your smith’s tools as an action to revive it, provided you are within 5 feet of it and you expend a spell slot of 1st level or higher. The steel defender returns to life after 1 minute with all its hit points restored.