Iratus: Lord of the Dead... If you felt that Darkest Dungeon had too much a priori knowledge required and wanted something with (slightly) more disposable units, more combat, and less mucking about in town, this isn't bad for EA.
Narratively, you're some necromancer killing your way out of whatever hole you were sealed in, or something like that. Not something that really matters.
Similarly to DD, you've got a town layer and a map layer. The town layer is pretty important, mostly giving you post-combat buffs like healing up your units or extra items. The map layer consists of one-way branches and you can see what's there, which is where a bunch of comparisons to Slay the Spire come in. No backtracking, no resetting. You're on rails to advance.
Unit creation is fairly interesting-- there's like ten different units, each of which have 5+1special skill. Each skill can be upgraded once: For example, one skill, by default, is a knockback. The upgrade either raises its damage or changes its knockback to a stun. Units are assembled from pieces, and each piece has its own stats which buff the finished unit (which you can upgrade later on, but you lose the piece currently installed). Units also have their own levels, which determine how many skills can be upgraded (and maybe stats; not sure). Then they have two equipment slots, of which items can be fairly potent-- regen whenever they change position, for example. On top of all this, you, necro boss, have your own levels which unlock active skills and passive buffs, and your own set of equipment. There's also a semi-rare drop that instantly allows you to upgrade a unit's level. So if a unit dies, you can bring them up to speed fairly quickly. However, if you spent a ton of resources upgrading their parts... you're out of luck there. (Imagine playing DD if you had to do the most advanced areas without leveling fresh units first... the quick boost is a tidy idea.)
Mechanically, the combat is nigh identical to DD, with two additions and a few tweaks. You've got a rage meter that goes up with actions that lets units use their specials, and a mana bar that goes up by completing battles that allows for non-unit spells. It's still 4v4 fights with positioning, buffs, etc.
So, the downside: It's early access. Balance in act 2 is kiiiind of iffy. I lost my party to a group that could drop a stacking party-wide effect that does like 20+ damage per turn. My tankiest unit had 90hp. Related to that, their nomenclature could use cleaning up, because that effect that killed me? Was actually classified as a debuff, despite not being marked as one, so I could have recovered if I used my debuff clearing skills earlier. Looking around, most of the complaints are based on balance issues, so... normal EA stuff.