RTF is a global modification that replaces all towns in the game.

You can create a standard golem from ordinary iron, an improved version from twilight steel, and an alternative version from some metal from the seventh game (like dragon steel).

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You can also put a small head with a hole in it, like in the seventh game, from which light will flow.

In general, I would replace the boring giant with a golem, and leave the manticore, as they added variety to this faction, or in this mod, you could give the dwarves the old, good griffins.