From The Heroes of Might and Magic III wiki

Town: Neutral

[[Image: ]]	Attack Skill	13	Damage	10-14
	Defense Skill	12	Health	60
	Speed	5	Shots	0
	Growth	2	Cost	750 gold
Special: 95% Damage Resistance from Spells

[edit] Dwelling

Diamond Golem is recruited in Golem Factory but only on the Adventure Map.

[edit] Upgrading

Can't be upgraded.