Here's the original "How to Train Your Flesh Golem" quote I always use (no guarantee its what he used of course):
Selrahc said:Oh, Flesh Golems have some use beyond that. Without including anything that requires heavily advanced technology, like merging in Krakens from OO Druids, experienced horsemen from Ride of the Nine, Shadows for Invis or Beastmasters, there are a lot of tricks you can play to get a pretty pimp Flesh Golem.
Firstly, merge in a unit with a higher base strength without any promos that buff it. A ranger will do nicely here. Golem is S7. Secondly, merge in a unit that has a higher base strength but does have promotions which buff it. A ranger with poison blades. The golem gets a strength increase from the higher strength, then adds the promo. Golem is S9. Now start throwing in Strength increases from other sources. Metal promotions, Flaming Arrows, Mutations, Nightmares, Sheut Stone. Do it from the cheapest units you can produce that have access. Warriors for mutation spamming, archers for flaming arrows etc. This should leave your Golem with a rather juicy base strength, somewhere around 14. But with only the promotions available to low xp units, and no way to gain more due to lacking a unit class. That's where the next step comes in.
If in the late game, you have been following a religion like Order or Kilmorph, and have an experienced hero like Valin or Bambur sitting around, you can be tempted not to change to not lose an experienced hero. A flesh golem gives you the chance to dump all those powerful promotions into an even more powerful chassis, and give you more freedom in picking your religion to boot. But what if you don't want to part with your hero? What if you're happy with your religion. That's okay. If you took the simple step of preparing some priests earlier. Take 3 for preference. They should be sitting with around 20xp. Capable of reaching level 5. Promote them up different lines, then merge them. Your golem should now be highly elite. But Selrahc, you're saying, who can afford to keep 3 experienced priests sitting around doing nothing? I've been fighting wars. That's how I got to the late game in the first place! In that case find one of your more elite units and merge him in. This is definitely an upgrade.
For the last ingredient, train yourself up a hawk and merge him in. Your little Frankenstein can now fly! He's all grown up and ready to leave the nest. Add Marksman promotion as preferred.
So what's the cost, what's the result? Cost: 2 rangers (Strength, Strength+Poison weapon, Mobility 1+2, Sentry 1+2) 1 axe (Enchanted Blade, Iron Weapons, City raider 1+2) 1 archer (Flaming arrows, City defence 1+2) 4-5+ warriors (Mutations, anything up to 2 promos for melee) 1 obsolete religious hero (or) 3 priests with xp to spare (or) 1 elite unit 1 Hawk Assuming all units are fresh built, going with 3 priests that is 905 hammers. Potentially if you're dumping old obsolete units then the actual cost is much less.
Result(priest version): S14, Move 5 C4, Drill 4, Blitz, Flying, Medic 2, March, Empower 5, Enchanted Blade, Poison Blade, Iron Weapons, Strong, Flaming Arrows, Mobility 2, City Raider 2, City Defender 2, Shock, Formation, Cover, Scourge, Light, Heavy, Sentry 2, Commando, Command 3, Cannibalize, (Resist Fire, Immune to Disease, Resist Cold, Resist Lightning, depending on mutations. These ones probably aren't worth making too much of an effort for while Blitz, Cannibalize, Light and Strong are all fantastic).
Is it worth the investment? I don't know to be honest. But you can make one hell of a superunit.
If you do happen to have OO druids, then the base strength of the unit rises to 22, while also dumping the 300 hammers of unit investment in rangers