I have a quick question about the choices of game speed. Do they change things like unit production and research speed, or just the amount of years each turn equals?

I ask this because I would like to make it so every turn means less years, but have research/unit production/etc. all take the same amount of turns. I find most my games are just finally rolling by the time the game ends, I would like to slow down the progession a bit.

Thanks in advance,

Just the number of years. It kinda-sorta makes sense if you consider the progress of civilization in general to result in really big efficiency increases. I don't know whether this can be modified by editing an XML or Python file. You can slow the entire game's tempo down, though.

Different speeds change years, research rates, chop yields, culture growth, food growth. Just about everything. It's really designed to have more time with each era without imbalancing the game. I've played normal-speed games where my unique unit had an advantage for about 10 turns maximum. On epic speed, I'm playing a game right now where Cho Ko Nu alowed me to take out three rival civs.

On the longer game speeds you still gain the same commerce, hammers, beakers, and everything else but what you buy with those things (research, trades, hurry production, population increases, etc) all scales up.

Things like buildings and wonders seem to take about the same relative amount of time, while units seem to take a bit less (I once saw a figure of 33% relative production speed increase, but I don't know if this is true or not). Gold hurry costs also seem less to me, but again, that's just my opinion and I can't show you any numbers to back it up.

However, everything still MOVES at the same speed. I love marathon because it has a few effects I like

- Wonders usually take around 40-75 turns to build. Make sure you're sure before you build one, because you can't hurry it.
- Units have much, much more time to go out warmongering before they're obsolete, making certain units that have otherwise short usefulness windows (warriors, musketmen, grenadiers, knights, macemen, and cannons all come to mind) valueable.
- Since it takes longer to replace units, there's more emphasis on taking care of the ones you have, hence a greater emphasis on siege warfare and grinding down defenses before you attack. I'll never throw a catapult (or any siege weapon) at a city on a near-certain suicide mission just for the collateral damage on normal, I do it all the time on Marathon. Same with starting a war, pillaging everything in sight, and calling a ceasefire while you build a real invasion force.
- This means the units you have get more experience. Which means it's usually more worthwhile to upgrade them than delete them and rebuild, which seems more realistic to me.

If I'm going for culture or space race I'll still play Normal though, since that game speed caters more to a peaceful style than a warmongering style, in my opinion.