I finished a full single player campaign of Warlock 2 the Exiled last week. Overall I enjoyed the game and recommend it but it does have some shortcomings and threatened to become tedious at times.
The game play is almost identical to the first Warlock but Warlock 2 has a wider variety of units and spells and a more defined single player campaign. It looks like a fantasy version of Civ V but there is far more emphasis on combat and very little emphasis on things like trade and diplomacy. The large game world is spread across a dozen or more randomly generated shards that are connected via a network of portals. These shards are beautifully rendered with a lot of variety of scenery and resources.
The tactical turn based combat is very good good with a wide variety of units and abilities. You are a great mage so you can support your units with spells that have powerful effects on just about every aspect of the game. I imagine it makes for an enjoyable multiplayer game although I have no idea how many people are still playing.
The single player game is somewhat let down by weak AI. Fighting NPC mages presents very little challenge but plenty of tedium as you slowly grind your way across the shards. Happily the default campaign is more challenging because it uses the age old trick of substituting ridiculously powerful monsters for decent artificial intelligence. In order to overcome the "United One" you must first find a way across the portal network to his lair. This encourages exploration of the shards. The monsters get every more powerful as you approach the final lair so you cannot neglect economy or development in order to have any chance against the final bosses.
The unrest mechanic is a new feature since the first Warlock which adds a very interesting twist to the strategic game. If you own more than given amount of settlements unrest will cause increasingly severe penalties. At the start of he game the limit is only five which you could easily use up on a single one of the more than a dozen shards. You can increase the limit through research but even by the end of the game I could only build a dozen settlements. This has a huge influence on the strategic game forcing you to make hard choices about which towns to keep and which to abandon. If you decide to let a town gp you can convert it to a special settlement which will still provide a small amount of resources but you can no longer control it or use it for recruitment.
The unrest limit means that it isn't possible to steam-roll over the shards capturing all before you. It also means that it is somewhat pointless going to war with the npc mages for territory. This is probably a good thing. In my campaign I ended up allying with all of the npc mages in my quest to overcome the United One. This may have been a mistake however because the poor AI meant my allies were more of a hindrance than a help they tended to send swarms of weak units around after me blocking critical access points and grabbing the loot from monster lairs after I had done most of the fighting. Worse again allying with an npc immediately activates every shard they are on which greatly slows down the time between turns.
The final battle is against four ridiculously overpowered "lieutenants" and it is a classic case of Contractual Boss Immunity as they are immune to a lot of the standard spells and abilities. Nevertheless I eventually managed to overcome them with a few ridiculously over-buffed heroes of my own. Some of the buffs came from spells but a lot of them came from special equipment that could only be made in certain regions due to the availability of special resources. The need to build or capture settlements in these regions while staying under the unrest limit became one of the dominant features of the game for me.
The campaign took me about fifty hours. Initially it was exciting as I got to grips with all the features but I found the long mid game quite tedious as I trawled across the shards fighting fairly weak monsters and doing my best to stay out of the way of npc mages. It was only when I reached the final shards that things got interesting again. The increasingly difficult monsters forced me to reconsider my strategy and my tactics.