If you enjoy strategy games and like a challenge, you will really love Eador.
The game involves you taking over "shards" in grid-based expansion-style gameplay similar to the Civilization series. Each conquered shard offers bonuses to you in your quest to take over the broken world. During unit battles, however, you will move to an actual level where your armies must fight - slightly similar to games like the Disciples series and Age of Wonders. The battles, however, are a bit more basic compared to those games (you are put into a top-down style map grid and can place your units prior to the start of battle).
The aesthetics of the game are nice, there is good detail in the area tiles and the unit models are decent considering the large availability of characters to recruit. The sound, music, and effects of things like activated skills and magic spells are also decent.
There is a lot to do in Eador, and the learning curve is pretty high if you are not familiar with strategy games. During your turn, you can hire "heroes" who act as your generals for your armies. The game incorporates a karma system where "evil" units like skeletons and "good" units like dwarves will stack and provide bonuses if your army has only one type of karma (so mixing the two will result in negative attributes).
You can "explore" each tile if you own it (up to 100%) and doing so may yield things like an adventurers guild that provides higher-tier characters for recruitment, various ruins or areas for you to fight monsters and receive treasure (there are A LOT of these), etc. Be warned, however, that is is not always advisable to explore your tiles to 100%, especially if you only have one hero because your enemy will surpass you in both troops and tile ownership very quickly. I think this contributes the most to the difficulty - when I play strategy games I am usually very good because I have a good balance of turtling while harassing, howver, in Eador the cost for subsequent hero recruitment increases substantially, and you can only move an army if a hero is leading it.
There are a lot of different buildings available to be built, however, there is a limit to how many of each kind/tier can be built. For example, the "military" buildings each provide a single unit (archers, spearmen, etc) and will also provide either "good" or "evil" units, , but you may only build 4 out of 9 buildings (if I recall correctly). At the next tier, you can only build according to what you have previously built (and this leaks over to other "types," like market/armory buildings). You may only build one building on a tile per turn.
At the initial stages/shards, the AI is not too difficult, however, quite early on you will quickly find your enemy to be very unforgiven. If you slack in your expansion and troop building, you will soon find the AI's troops right outside your borders. Once you take over a tile, you can build a fort in order to garrison troops - if you don't you can hire a single "guard" unit to patrol around the tile and defend it from invaders. This makes it a bit easier to reclaim (or lose) tiles.
There is variety in how to take over tiles as well, depending on what kind it is. For example, some village tiles will join you peacefully if you pay enough gold, and they will provide a free "guard" unit as a result. Others may offer missions and join you upon completion.
The battling system is decent, but if you are used to the more complex battle system in Age of Wonders or the Disciples series, you might not like this as much. You get flanking bonuses against your opponent if you can maneuver behind or to the side of them. Your hero is critical to victory here, as each type (ranger/scout, mage, general, warrior) will affect your party in different ways. The wizard, for example, is very versatile (depending on what magic buildings you invest in) because he can heal, buff, debuff, and use offensive spells. He can also summon units, and investing in specific skills can allow you to keep those units after battle (if they survive and you have space in your party). You unlock more party slots as your hero levels up.
The leveling system is pretty interesting, you get 2 options for your units (for example: +health or +morale), and sometimes your units will also be considered for awards/medals. These will provide extra bonuses (like extra damage), however, they will also increase the upkeep (and this can be significant in the beginning when you do not have much income).
Overall, the game is very fun once you know what you are doing, and persisting over the learning curve will allow you to enjoy the unique challenges Eador offers.