Usually, XCOM 2 is a game where you battle aliens in missions, pray to God (who is probably also an alien) that your precious troops don't get perma-killed and purchase upgrades between missions. This mod changes that entirely. This week's popular new XCOM 2 mod is called Wave COM. It's a survival mode, but with an XCOM twist:
WaveCOM is a different style of XCOM, where you take your squad of 4 rookies and survive as long as you can against gradually stronger waves of ADVENT and Aliens. Engineering and Research is available to you, with all the time based build times translated to supply costs.
So basically, you slowly get stronger as a match goes on, but so do the aliens. Then you die.
As someone who hasn't played XCOM 2 in a couple of weeks, this feels like the kind of thing to bring me back aboard the Mothership to be mercilessly probed and reduced to ash once more. Rather than adding More to the old formula, it's a new twist that will at least be fun for a few hours.
While we're on the subject, have you found any other XCOM 2 mods that substantially alter the game and its progression?