After the arrival of my Merc Reinforcement pack - Stone Golems have become my favorite Merc common units after Spear Grounders. Although it has the weaknesses of not being able to attack when moved two spaces, it's 3 life points and 2 attack value is highly useful to factions that play "turtling" strategies like Vanguards and Deep Dwarves. With Vanguard using Stone Golems, it can easily provide VG's players the opportunities to use their Priests' abilities and Divine Strength.
Furthermore, it can provide the needed "defensive" support to factions with fragile factions such as Phoenix Elves and Benders. For the latter, I like how Stone Golems can be combined with the Controllers abilities which can help push Stone Golems another space after the Controllers attack. I like the fact how Stone Golems can be an advantage additions to PE deck when it can combined with Fire Beasts to provide common units with more staying power on the board to stop enemies from advancing towards Prince Elien.
It is also interesting for JE player with a custom deck using Stone Golems and Archers. Stone Golems can act as front-line defensive units while the Archers can remain at the back shooting their arrows without having to worry of being attacked and killed.
It can be combined with GD in combination with Guardsmen and Tordok with greater staying power of the common units on the board. In addition, it would work well with TO complementing the use of Chargers and Thwarters in the deck that pressure for offensive attack to give time for Stone Golems to gradually move forward.
What other factions do you think that Stone Golems can be most complementary and why will you sub them into the other factions? Would be interesting to hear some of your ideas.