This is rather unfair, I am aware, but the main reason I don't play with mods is because they rarely reach the level of Firaxis' work when in comes to aesthetics. There are very talented people out there, including in this very forum, who have made brilliant mods for Civilization V but, in the end, it just feels jarring to have beautiful, animated, fully voice-acted with an orchestral soundtrack leaderscreens in one hand, and all of the sudden a static, silent leaderscreen comes up. To me, it breaks immersion and flow to the game. This is obviously not the modders fault - obviously they don't have access to the resources Firaxis has, and even if they did, Civilization V makes it hard to mod that in (if I remember correctly, only recently did we have some sort of 3D leader mod). If anything, it's more my fault for being spoiled! I guess I could technically just play as the mod civilizations, that way I wouldn't have to deal with their leaderscreen, which brings me to the second reason. Playing mods that change the gameplay, to me, feels like cheating, and I don't like to cheat. I don't consider it cheating when others play modded games, but I feel like I'm breaking the rules by doing so. Playing as a civilization that does not exist in the game? Cheating, specially more so when the mod civilization is unbalaced. Using a mod that changes a few rules for everyone? Cheating, specially more so when it gives me a bonus when compared to the original game. Things like InfoAddict or the Civ4Diplomacy mod (however that one was called) just makes it seem like i'm breaking the game and accessing the developer tools mid-game, or loading up the WorldBuilder, or whatever... (again, I'm not saying it is cheating, or making any sort of moral judgement for those that do play with mods. I'm just saying that, personally, I don't feel comfortable with myself doing so, which hinders my enjoyment of the game) So now we are only left with mods that change aesthetics, like the Extra Religions mod, or the one that gives the religious icons colors, or the Ethnic Units mod. To me, though, those changes are not enough for me to justify losing Achievements, and longer loading times. I would totally play those if it weren't for that. This is also the reason why I like the way Paradox handled mods in EU IV - cosmetic mods allow you to still play with IronMan and get achievements, but gameplay mods don't. I actually play with the Better Terra Incognita mod in EU IV, since it changes nothing but the graphics, and makes me lose nothing for that. I wish Firaxis had made that for CivV as well... So, in other words, I'm an hypocrite and a spoiled brat! I guess I don't deserve to play with mods anyway!