The Gear Golem is an interesting gate summon, but it's just flat by far the weakest of the gate summons.
Comparing:
Gear Golem has:
38AB, 21-41 damage on a 20x2 attack
27/23/20 saves
47 ac, 474 hp
Immunity to spells below 3rd level, 32 SR, immunity to paralysis, slows
Regeneration, 6DR, and some unknown damage immunities and a weakness to electrical
Flesh to stone spell
Deva Has:
38AB, 21-46 damage on a 17-20x3 attack with a stun chance on hit
28/20/25 saves
44 AC, 449 hp
22 SR, immunity to spells third and lower
6DR, immunity to cold/acid and DR vs electrical/fire
Word of faith spell
Protection from evil aura
Verdant Prince has:
38AB, 20-49 damage with 10-20x3 attack
Less fort but otherwise similar saves/hp/AC to devas
22 SR
Nature's balance/imp invis spells
Issues with Gear Golem:
- Flesh to stone is a waste of a spell, it's DC isn't high enough and it stand around doing nothing useful for a round
- Weakness versus electrical and lower will save make it a lot less tanky
- Surprisingly for a golem, it lacks construct immunities
- It has the weakest attack damage of all summons
- It appears to generally be slower, but that might be perception bias
Positives:
- It's immune to acid fog/grease/entangle which no other summons get
- 32 SR protects from WoF scrolls pretty well - not any better than 32SR on planar conduit T6 summons though.
Possible improvements?
- Gear Golem is niche at countering spells, it could have higher SR, like 40, making it really hard to get rid of. This makes up for it being generally weaker, because it's very hard to remove
- Gear golem isn't going to do much damage in a fight because it's rounds/level; maybe it can be the only gate spell that lasts longer - especially as it's a unique golem and this would be fun to RP rather than having formians
- The gear golem could have some on-hit effect, such as a stun like the deva, to help make it more viable in battle
- Definitely please remove the flesh to stone so it can fight instead of stand there
- Give it construct immunities so it doesn't die to crits/death magic