Second wave is free to download today. It adds a bunch of extra modifiers to the game (e.g. random soldier stats, increasing costs of satellites) that can be set when you start like iron man mode is. You need to unlock them though, you get four to start with and unlock 4 more for each level of difficulty that you complete. Looks like there's some interesting stuff there, modders found it ages ago but not everything was implemented fully. Here's the pc gamer article.

http://www.pcgamer.com/2013/01/08/xcom-second-wave-options-officially-released-by-firaxis-patching-in-tuesday/

Has anyone played this yet? I'm wondering if the modifiers apply to the aliens as well as the squad. Specifically red fog I think it was, character mission performace degrades based on damage taken. This could really change some things in the game, like target priority.

I only just saw this thread, I'll be downloading it ASAP on the 360 and giving the options a go. Once I've gotten familiar with them I'll tell you what I think. It certainly beats three scripted council missions.

I haven't tried it yet. I wanna beat the game on classic ironman first. However I don't think I'm ready for impossible so ill probably use a few of these.

I really like the random starting rookie stats, random income from countries. Another one makes every flanked attack a critical one which could be very interesting. But some of the mutators just seem mean.

Ya some of them are fuckers all right. I'm interested in the ones that make things a little more random like the random starting stats. They could liven things up a little.

Man, if this had been available from the start, I would have torn my hair out trying to play with some of these. I'm glad they waited until post launch for these.

Ok, finally some thoughts on a few of the new options:

Damage Roulette - certainly adds a level of unpredictability into the combat, which you'll either find fun and surprising or the biggest load of bullshit ever. Throwing a grenade into a group of Mutons only to see it do one damage a piece is not a nice turn of events on Classic Ironman. Much like anything else in XCOM that is based upon probabilities of success, don't ever expect this option to work in your favour.

Not Created Equally - a nice little touch that makes your soldiers feel more like individuals. Although their position in battle will still largely be determined by their class, knowing who naturally has the highest aim adds an extra layer of strategy, however thin it may be.

Hidden Potential - a similar idea to Not Created Equally, with similar results. If you like customising your squad and making them a little more unique, this is a neat feature.

Red Fog - @arabes asked me to give this one a look to see if it effects aliens as well as your team, but to be honest it's nigh impossible to tell. I suppose it's a nice option if you want yet another way for a mission to go wrong, or if you want Enemy Unknown to feel a little more like the original, but I'm not a huge fan. If my soldier has been injured then the situation is probably bad enough to begin with.

Marathon - does exactly what it claims to do, so if you want one long tough game more about seeing how far you can get than actually winning, then this is for you. Personally I quite enjoy it as it makes progress feel much more eventful, and is a better alternative to just playing through the game multiple times as it is all one consistent experience.

@mustachio: Thanks for checking that out dude :)