Might of the Master. The following numbers increase by 1 when your proficiency bonus increases by 1: the iron defender’s skill bonuses, the bonuses to hit and damage of its bite, and the number of hit points restored by its Repair action.
Vigilant. The iron defender can’t be surprised.
Iron Defender. In combat, the iron 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, or Help action.
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 iron defender returns to life after 1 minute with all its hit points restored.
Bite. Melee Weapon Attack: +4 to hit, reach 5 ft., one target you can see. Hit: 1d8+2 piercing damage.
Repair (3/Day). The magical mechanisms inside the iron defender restore 2d8 + 2 hit points to itself or to one construct or object within 5 feet of it.
Defensive Pounce. The iron defender imposes disadvantage on the attack roll of one creature it can see that is within 5 feet of it, provided the attack roll is against a creature other than the iron defender.
This metallic creature resembles a hound, a cougar, a bear, or another four-legged creature of your choice. It is friendly to you and your companions, and it obeys your commands.