Might of the Master. The following numbers increase by 1 when your proficiency bonus increases by 1: Alexia's skill bonuses, the bonuses to hit and damage of its attack, and the number of hit points restored by its Repair action. Vigilant. Alexia can't be surprised.
Horn. Melee Weapon Attack: +4 to hit, reach 5 ft., one target you can see. Hit: 1d8+2 piercing damage. Higher Levels: (damage bonus increases with Artificer Proficiency Bonus) Repair (3/day). The magical mechanisms inside Alexia restore 2d8+2 hit points to itself or to one construct or object within 5 feet of it.
Defensive Pounce. Alexia 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 Alexia.