I'd say that it was the Parkour mod, but I can't remember if that was the exact name. In any case, it was simple and fun, not quite as intense and complex as some of the others.
On the other end of the complexity spectrum there is Hexxit, which I rather enjoyed.
IndustrialCraft2 - Because machines thats why
BuildCraft 6? - Because of the pipes, quarry
Of all those 3 it would be the Aether2 :3
On the other end of the complexity spectrum there is Hexxit, which I rather enjoyed.
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1: Description Tags, reminds me of Strange weapons and the description tag from TF2.
2: Not Enough Items, not for just the recipes, but for the other neat features it has.
3: I am also in love with SFM (Steve Factory Manager), Who needs pipes?
Last but not least, every mod! Cause' you can't have just 3 favourites! (Yes, I use the other English)