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

where can I find them? I only found the basic ones, phoenixes, wolves, mummies, and all the regular ones that were in the original game.

Download mods for the new creatures. If you have the EWA mod installed, they will be in UnitPlus.pak and MegaPack.pak (or something like that).

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are they all found using the same method?

Yes.

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And yes, let's not clutter the thread. If you want to ask something else (not related to the topic), please send me a private message.