I really like Blades in the Dark, so much so that I'm running two games of it right now, and it's my go-to system. But it's tightly focused on a group of scoundrels doing crimes to survive. Band of Blades stretches the BitD core to cover a gruesome game of military horror and survival, and does so with aplomb.

You are the Legion, a military unit with a storied pedigree. The world is beset by an army of undead lead by the Cinder King. Your unit, along with the divinely gifted Chosen, must brave the hazards of Aldermark to make it to Skydagger Keep. The setting is low magic gunpowder fantasy inspired
by Glenn Cook's Black Company series and Game of Thrones, where muzzleloading muskets, swords, and unsettling and uncertain magic face off against human and inhuman foes. It's nicely generic, easy enough to say "oh, this is like that from popular culture", while still having its own unique flavor.

The mechanics are inspired. Players serve as the major officers of the Legion, commander, marshal, quartermaster, lorekeeper, and spymaster, making strategic decisions about where to advance and what missions to pursue. On the front lines are squads of rookies and soldiers, aided by elite specialists. This is emphatically not a game about getting attached to people. War is hell. War against the undead is literal hell. Casualties will be high. Your job is to get the mission done.

The core of the game is much the same as BitD (d6 pools, Stress & Pushes), but characters are more fragile with only 6 Stress. Gear has to be picked before leaving on a mission, you are not devilishly lucky scoundrels. To compensate, Specialist actions aren't rolled-they're just declared. But you'll need these abilities to even stand a fighting chance against powerful Elite undead and fearsome Lieutenants.

Scene to scene, it's BitD and it's going to be good. Having read through, I can't be as confident in the meta level of casualties and resources. Secondary missions seem particularly punishing, given that they're resolved with a single toss of the dice and can have whole squads and specialists killed and missing. There's a fine line between 'desperation' and 'death spiral', and this may be a game where failure even on the campaign scale is an option. The Legion solves problems in part by throwing bodies at them, and the game requires a fair bit of buy-in for people who will likely be playing a different character every session. This is also a combination rulebook and campaign; you will be making your way to Skydagger Keep, and assuming you survive, you'll be scored (possibly for a future Season 2 expansion), so GMs looking to tell a 100% original story will have to do more work, compared to the more sandbox nature of other BitD variants.

But it looks good, reads great, and has lots of neat ideas. In particular, X-COM the RPG is a definite possibility.