Bound. The golem is magically bound to its creator. As long as the creator and it are on the same plane of existence, the creator can telepathically call the golem to travel to it, and the golem knows the distance and direction to its creator.   Structural Constitution. You have reinforced your Golem with layers of protection and redundant systems. Its Constitution ability score increases by 2, increasing its stability and durability. If, after taking this skill, the golem's Constitution is 16 or greater, it gains proficiency with Constitution saving throws. If, after taking this skill, the golem's Constitution is 18, it gains advantage on Death Saving Throws.   You can take this upgrade more than once. A golem's maximum Constitution ability score is 18.   Defender Protocol. You build in a protocol response into your golem to defend its master. The golem gains the Protection fighting style.   Protection When a creature you can see attacks a target other than you that is within 5 feet of you, you can use your reaction to impose disadvantage on the attack roll. You must be wielding a shield.   Grappling Appendages You install an additional pair of grappling appendages taking a form of your choice. For the purposes of grappling, these serve as two additional free hands for your Golem. Additionally, your golem gains a climbing speed equal to its movement speed so long as it is not using these appendages to grapple.