XCOM: Chimera Squad
Chimera Squad tries to boil down the essence of XCom. In some ways, it is more streamlined. In others, it does not have as much soul.I'll assume people are pretty familiar with XCom, so I'll just address the differences here. When I write XCom I generally mean XCom 2.
Tone
XCom tries to be gritty and realistic, given the ridiculous premise of alien invasion. Chimera takes a more lighthearted approach. Instead of 3D cutscenes, it has comic book panels. Where random commentary in XCom was serious with some humor, Chimera is more humor with rare bits of seriousness. XCom is often very cheesy, but it takes itself seriously. Chimera Squad is much less so. This had the effect of me being far less engaged in the plot.
Operatives
In Chimera Squad there are 11 different operators. In XCom there are 5. However, the roles in XCom are far more customizeable. The end result is that it is far easier to build tailored squad in XCom.
Another big difference, is that you only have a fixed number of operatives in Chimera Squad. You start with 4 and acquire 4 more often the course of the game. The operatives are always healthy enough to join a mission, although they can accumulate enough wounds so that you will voluntarily hold them back to heal. Basically this means you could play the entire game using only 5 squad members (4 for the mission and 1 to heal or train). For me, a big part of the charm of XCom is juggling wounded operatives.
Missions
The biggest change in Chimera Squad is the breach system. Encounters are played out sequentially. This counters my biggest complaint about XCom, the possibility of activating multiple pods at once. However, the actual encounters have small maps with few real tactical options. Furthermore, there is no strategic planning possible. You can't choose to sneak around the back, or send an operative to flank. Also, it has one of my biggest pet peeves in games, which is when you can heal during an encounter but not between encounters. I found myself intentionally delaying ending an encounter to give my healer time to top everyone off. This effect isn't so bad in Chimera Squad -- only one of the roles can heal, and it's not required. Also, you can change the settings to automatically heal between encounters. Perhaps I could try playing where full-heal was enabled on missions when I send the healer but not otherwise. It still doesn't help with the suit of armor that slowly heals the person wearing it.
Overall
In the end I could finish my first campaign because I wasn't engaged. Perhaps I needed a harder difficulty setting. But really, the tactical battles were not deep, there was no exploration and strategy during missions, and the "world map" decisions were not especially deep or interesting. There is a lot of competition for tactical games out there. Chimera Squad is quite good at that and is cheap, so in the end I would recommend it for that. However, I hope XCom 3 has a lot more meat to it.
Another similar tactical game is Into the Breach.
