Creating your own maps and playing them online is always fun, and I have a few mods which let you edit unit properties, for instance prism dogs, chrono apocalypses etc, you can also give units heavy regen armour, upgrade speed, upgrade promotions (ie past general level and up), change country names, unit names, unit images, the whole works.
You can really have some fun with it, if you likethe sounds of any of them, pm me and I'll get them to you.
Only flaw is that you need to send the online opponents whatever mod you are using (maps can be transferred in game, other mods need to be sent by other means), so there's no 'making an unbeatable army and going undefeated on tournaments' (sadly

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