Der PH
Combat Smurf
Don't know if I'm the first to come up with this idea, but if not: So what?
AFAIK it is possible to make not only strategic resources a requirement for building certain units, but also luxury resources.
Since the luxury resources are not (more or less) evenly distributed over the map, but clustered in certain regions, they mostly are only available to one or a few civs (before the establishment of trade routes, of course).
This way it could be possible to insert units that are only available for one or a few civs, randomly appointed by the distribution of luxury resources. Could make the game a little bit more interesting.
Of course this works only in the ancient and early medieval era, before everyone has trade routes with everyone else, but that's no problem, if the relevant units are from these periods.
First ideas what units this could be:
Ivory: Early elephant rider (obviously), available with horseback riding, 3/2/2, +1 HP, very expensive! (I already tested this as a carthagian UU, strong, but not invincible)
Incense: A religious motivated unit, available with theology, maybe the crusader (5/2/2) or the fanatic (?/?/?)
Furs: Hunter (Scout with 1 attack and defense?)
Dyes: Mercenary hoplite (from Kryten's hoplite collection), (1/3/1) -1 HP. Why dyes? AFAIK dyes (purple) in the ancient world were mainly produced by the phoenicians, who hired lots of greek mercenaries. Not a stringent connection, but better than nothing!
Gems: Swiss guard ( 3/3/1, pikeman replacement)
Silks, Wines, Spices: Ideas wanted!
Comments, ideas, rants?
AFAIK it is possible to make not only strategic resources a requirement for building certain units, but also luxury resources.
Since the luxury resources are not (more or less) evenly distributed over the map, but clustered in certain regions, they mostly are only available to one or a few civs (before the establishment of trade routes, of course).
This way it could be possible to insert units that are only available for one or a few civs, randomly appointed by the distribution of luxury resources. Could make the game a little bit more interesting.
Of course this works only in the ancient and early medieval era, before everyone has trade routes with everyone else, but that's no problem, if the relevant units are from these periods.
First ideas what units this could be:
Ivory: Early elephant rider (obviously), available with horseback riding, 3/2/2, +1 HP, very expensive! (I already tested this as a carthagian UU, strong, but not invincible)
Incense: A religious motivated unit, available with theology, maybe the crusader (5/2/2) or the fanatic (?/?/?)
Furs: Hunter (Scout with 1 attack and defense?)
Dyes: Mercenary hoplite (from Kryten's hoplite collection), (1/3/1) -1 HP. Why dyes? AFAIK dyes (purple) in the ancient world were mainly produced by the phoenicians, who hired lots of greek mercenaries. Not a stringent connection, but better than nothing!
Gems: Swiss guard ( 3/3/1, pikeman replacement)
Silks, Wines, Spices: Ideas wanted!
Comments, ideas, rants?
Perhaps fine silk can be used as a camouflage... 
