XCOM 2: War of the Chosen

This is the hands-down first-rate king of expansion sets for an existing tactical game. Firaxis wanted to do expansions and refinements for the successful XCOM 2 game. The resulting project nearly re-wrote the game, instituting changes to XCOM 2 that definitely changed and expanded game play. This review concerns the actual War of the Chosen modifications. For the baseline game, see my separate review.
War of the Chosen (WOTC) is an excellent expansion for the XCOM 2 game. You do need XCOM 2 to use WOTC; if the price tag looks high, wait for a sale or get a bundle that gives you some bang for the buck. The story is still the same, but there are a few new features. The first is the addition of three specialized soldier types, each with an associated Resistance faction that is separate from XCOM, and which might have different agendas than XCOM. The game presents the new content in mission story form for the first playthrough. In a divergence from the original game, the second mission of March 2035 will not be a standard type, but instead will be new content named "The Lost and Abandoned". XCOM is forced to play mediator to two Resistance factions, the stealthy hunters named Reapers, and former Advent CQC soldiers named Skirmishers. The two factions stage a meeting in an old city ruined by the invasion, haunted by its zombified citizens. Just when it seems that differences will outweigh similarities, Advent shows up to remind everyone about "strength in unity". A third faction, the combat-oriented psi troopers named Templars show up later.
The three hero soldiers automatically generated are made to be representative fighters of their factions. The Reaper combines the best features of a stealth-build Ranger and a marksman-build Sharpshooter. A Reaper can be used to scout ahead and mark enemy pods, allowing the squad to get closer to the mission objective before revealing themselves on their own terms. The Skirmisher is an agile close-range fighter, armed with SMG and combat claws to overwhelm their opponents. They have a built-in grapple, allowing easier use of elevated combat before the Spider Suit gets researched. The Templar is psi-based melee hell on wheels, able to one-shot foes in the early game in a single slash, then dash to a safe position. Their psi powers diversify with advancement, but remain active combat focused, unlike the typical Psi Soldier. The other factions' gear advances with subsequent tier development as per the standard R&D. Each faction has a base that gives XCOM's ship Avenger a safe haven and provides a scanning bonus: the Reapers grant aditional Intel, the Skirmishers increase ship construction time, and the Templars provide accelerated healing.
The existence of differing factions puts a renewed emphasis on the strategic level of the game. Gaining control of regions and using them is more important, especially as the WOTC game is longer than the standard game. A Resistance Ring is now available for construction, and should be built as soon as possible. Why? The Ring allows for 1-3 soldiers to be sent on covert missions, which if successful grant resources, give soldiers better skill sets, grant tech upgrades, hasten research, or sabotage Advent progress. Sending Rookies on covert missions automatically promotes them to Squaddie, so there is no pressure to build the Guerrilla Training School first, which is practically mandatory for the standard game. However, missions can negatively impact a campaign, resulting in soldiers being wounded or captured by Advent. (That brings on a new covert mission choice: find the POW and set up a rescue mission.) Ut's also possible the operatives run afoul of Advent, and have to run for their lives through a Lost City, pursued by Advent hunters and the Lost themselves.
Since it is a longer game, the old XCOM technique of building several teams' worth of capable veterans has been officially added to WOTC. Soldiers that participate in multiple missions in a game month without a rest gain the Tired status. Tired soldiers can be sent on a mission, but they're more likely to get injured on a mission, are more likely to gain negative status, and will be given a mandatory leave from duty afterwards. Players who don't deliberately keep 3-4 teams in rotation as their character pool grows will see vital missions go undone because they have no healthy soldiers to send! But, soldiers who operate on the same team for a while also develop camaraderie in the form of Soldier Bonds. This mechanism allows two soldiers that create a bond to gain bonus actions when they are on the same mission squad. A Training Center is thus included for improving soldier bonds, and letting existing soldiers learn skills outside their specializations.
Of course, Advent isn't left out of the fun, and there is a new threat. "The Lost and Abandoned" also introduces the Chosen, three elite antagonists that put a face on the largely anonymous enemy forces. They are the Elders' special minions, charged with counter-resistance actions while the Elders work on the Big Plan. The Chosen are anime-level antagonists, powerful and skilled opponents with a high opinion of themselves and a desire to tell you all about it. They will randomly drop into missions, replacing a standard pod, and will proceed to taunt and torment the active squad, adding a new level of complexity to what is often an already complicated scenario. Ridding yourself of these dangerous pests involves using the Resistance Ring to locate the specific bases of the Chosen, and then raiding them like a story mission objective.
A third-party menace is the Lost, the wretched inhabitants of old cities that were ruined and mostly abandoned during the invasion. Contaminated and twisted by alien materials, the residents who didn't flee fast enough have become a zombie-like horde of mindless killing intent. That's right, XCOM has zombies again. Loud noises in a Lost City map are guaranteed to bring successive swarms of them, in increasingly larger numbers. (It's typical to meet at least 30 of them, and I have a personal best Lost kill score of 101, so you've been warned.) This makes the standard default tactic of making everything explode with grenades and rockets counter-productive, so it's best to send a squad that can shoot straight and run fast! On the bright side, the Lost will also target Advent opponents, which a clever Commander can put to good use.
Toss in a few new maps for both the new content and some random variations, and WOTC is worth the price tag. The game is longer and has some more choices to make, especially in the early game, but it's worth it. The replay value on all levels of difficulty has increased at an algorithmic rate, The DLC packs for the standard XCOM 2 game are compatible, so with the full package it's possible in WOTC to deploy a squad that includes a SPARK, a Reaper, and mohawked street fighter, and then be pursued by an Alien Ruler through a Lost City. (It was an absolutely crazy and dangerous mission, 5 soldiers including the SPARK wounded, 10/10, would do it again.)

Pratal Mox consistently missed 70%+ shots, attempted to redeem him at the final boss with a 97% killshot. He missed.

Honestly, I agree with pretty much everything XCOM obsessive Alec Meer wrote in his Rock, Paper, Shotgun review of War of the Chosen. If XCOM: Enemy Unknown was a streamlined but largely faithful remake of X-COM: UFO Defense, then War of the Chosen is the polar opposite, elevating the XCOM commandos into increasingly ridiculous superheroes who fight a wide array of aliens, including broadly-drawn supervillain adversaries who haunt you throughout the game.
It’s a very different game than XCOM 1, but this isn’t a bad thing; having played XCOM, it’s expansion Enemy Within, and XCOM 2, I was definitely ready for a shakeup, and I honestly found this more compelling than any previous game. I think the key is just the sheer amount of stuff packed into it; XCOM 2 already incorporated much from the base game’s expansion while adding in its own changes, and War of the Chosen adds in three additional classes, hero characters, and a variety of bespoke missions. The adversaries that can pop up in any mission (and are absolutely brutal in the early game) ramp up the tension and keep things varied.
It also readilly became apparent that the producers went out of their way to hire Star Trek: The Next Generation alumni to play all six new allied characters; thankfully, none of them phone it in.
I’m the sort of person who tends to play through an XCOM campaign just once—too many games and all that—but if I were to replay one, it would probably be War of the Chosen.

Had a "Very Difficult" mission where on turn four the Aliens and the Lost begun duking it out between themselves... and the Aliens thought it'd be a good idea to start using explosives.
They summoned a Lost swarm THREE TIMES. All that while my squad was camping on the roofs, still concealed, just watching the sh*tshow below.
Result? Mission passed, no shots fired, 80% of enemies killed. Brilliant. Just had to wait for the Lost to kill the Aliens and evacuate via Skyranger.

This is not a DLC, This is a damn new game.
+Rebalances elements from the normal game
+More lore
+More classes
+More customization
+ZOMBIES
+New enemies
+3 NEW BOSS-LIKE ENEMIES.
I can only see one downside, which is...
-duplicates the needed memory to install... (from 35 GB to 72 GB)
FANTASTIC PIECE OF WORK.

This isn't a review but more of a PSA.
If you're having trouble getting the game to launch or if you've seen the reviews and are concerned, get the XCOM 2 Alternative Mod Launcher. You can launch the game with it, still use mods, and it's just better than the default launcher in general.

To me, this is the best iteration of the modern X-Com games (X-Com: Enemy Unknown and X-Com 2 with DLC expansions).
Note that in "War of the Chosen" (this DLC) you will play the X-Com 2 game from beginning to end, this DLC will just give you much more stuff to choose from (weapons, armor, types of soldiers) and much more variation (mission layout, enemy types).
Thus, this DLC is NOT a continuation of the story in X-Com 2, but an "alternate" (and superior) way to play the game.
I especially enjoyed the addition by this DLC of boss enemies and the improvement to the level layout.
If you're thinking about playing X-Com 2, I'd definitely recommend the game - but get this DLC as well, and then just play the DLC version of the game.
You can choose to play this DLC version on the very first window that pops up when you start the game.