At the risk of losing my voice by shouting about Warhammer: Vermintide 2 every chance I get, here I go again. Fatshark's melee-centric co-op action game has made it over to Xbox One today. If you're buying it outright, it's $30 for the standard edition. If you have Xbox Game Pass, it's free with your subscription.
Even if you skipped the first game, Vermintide 2 comes highly recommended.
The sequel nails its core loop and sense of progression. It's inherently fun to mash on hordes of Skaven and Chaos with friends, and the steady loot drops will keep you queuing up "one more round" every time your group makes it back to base. Whether you're facing mindless grunts, special enemies that'll sneakily pick you off one by one, or bosses with oversized health bars, teamwork is a must. Vermintide 2 is best with friends who know not to wander off. That said, I've had decent success with randoms.
I've only focused on leveling one class for one character so far (the Witch Hunter), and I'm not bored yet. There's a bit of Diablo special sauce to powering up and perfecting your gear that has me hooked.
I suspect the PC version will see quicker updates, but don't let that stop you.