Civ2 & civ5, rest are forgettable.
Surprised that moderator encourages negative-talking.
Anyway I always wanted to write a rant about civ6 and now it is almost officially dead, it seems like it is a good time.
Not surprised that many people voted civ6, it is the newest and the shiniest iteration. It all started with the infamous Shafer vs Beach conflict from which civ5 release suffered. It resulted in Shafer (much younger newbie who was acting as lead designer) to actually behave classy, take a fall and leave a company. Firaxis acted like a true company and blamed the guy who left (iirc they stayed silent). Anyway, ultimately an old firaxis veteran (Beach) took the lead designer role.
First act is Brave New World (civ5 dlc #2 - first 100% overseen by Beach). Not so bad mechanics-wise. Only game became suddenly noticeable easier which was foreshadowing things to come.
Ed Beach likes (and designed) board games. Board games do not really have AI opponents like video games (solo automas do not count).
Personally I find Beach's design philosophy limited to two things: content pulp & fan service. "It sounds good? Let's do it." No consideration for AI, mechanics interaction, balance, strategy, whatever - game must sell, players must reach no-refund time and that's it.
Writing about civ6's AI is a bit like beating a dead horse. Extra settler at 6/8 difficulty, introducing combat bonuses for AI. Still can be overrun by barbarians even on relatively high difficulty.
Some AI opponents just become lethargic at 100-150 turns (I don't know if it based on individual leaders' behaviour numbers). Civ7 tries to fix it by limiting games to 100-150 turns.
However, what is worse is that AI was officially pushed to gameplay mechanics (by fan-favourited Agendas) and reduced to some silly numbers. Opponents have no personality, reduced to cardboards.
Just before civ6 release there was an "official" AI game (no human players game). Such games were popular at the time (civ5). However it was the biggest shoot in the feet for otherwise good marketing campaign. We could see all the flaws, no conquering, no unit upgrading...
To summarize, AI is no in yellow-zone "he, he, die stupid AI" but in red-zone "oh no, I bully a disabled". Though those zones are obviously personal.
Okay but what about military emergency? I believe it is one of the worst designed mechanic ever in the history of gaming. I don't mean that whoever came up with it or green-lighted it should be fired. I just hope they will learn from this mistake. When you have an AI that hardly stands on its legs you should do everything to hide it, not expose it. Watching AI moving zombie-troops through your territory just to die... Not a good experience.
That's the same reason why agendas are bad. AI can't comprehend a situation (oh no, you have no navy, pal!) and agenda system exposes its stupidity. Hide it!
Even small things like capturing settlers... (gone with civ7 - we are learning). Why introduce something that allows human players to make such impactful power swings on AI?
Music, they experimented with tunes based on era. It was okay at best. I believe it is gone from civ7. Good riddance.
Visuals. Not a single one of previous iterations had issues that civ6 so bravely introduced. Not a single one had issues with scale, world feel, or ask players to look at individual buildings. Not much to write about, some people like it, I don't. Ancient canal cities are probably the worst graphics that suppose to represent a city in the series.
Lenses are so bad that Firaxis disabled them for starting settler.
Leaders have detailed models and animations and yet... they are just cut-scenes. What is more you have to leave a cut-scene to be able to further interact with game. Double escape to make annoying popup go away. By declaring war you are not rewarded with a cool animation but a black mask fading - it is an initial game reaction to it. Lack of 3D background was also a downgrade.
Oh, a transition from dark to heroic age is a blatant attack on eyes.
UI/UX. That's where civ6 died for me.
Lack of options. You don't like lenses? You have to mod them out on your own (or select another unit...). Natural wonder discovery animations - again you have to do it yourself.
Hotkeys? Almost none. Ctrl-S, Ctrl-L? Forget, consoles do not have such things.
Lack of proper refresh. You make city changes and top panel do not display yields correctly. And so on.
Information is either hidden (wonder placement criteria hidden in civilopedia from top of my memory) or just straight unavailable.
In general UI mods are very popular in civ6 for a reason. Thanks, modders.
Unfortunately each time you want to introduce new mod, your game configs are obsolete. Just great.
However I can't explain why moving/interacting with units feel so bad in civ6. It is especially feelable when you autoplay X turns in fire tuner and then want to fortify/sleep units to process another turn normally. In civ5 it simply feels good and responsive. Civ6: each fortification is such a drag. After an attack you have an obvious delay before damage numbers float. Moving is also not as fluent as it should be. My only theory is that every unit action rechecks modifiers. More civilizations => more units and modifiers, more units => more modifiers and movements. That's where I believe performance issues lie. Civ7 limits number of players and also movement (railway station are airlifts, commanders).
I simply realized I intentionally do not build units/make wars in civ6 because interacting with units feels bad.
Monetization. Introduction of personas. Multiple leaders of civilizations that coincidentally are big video games markets (amount of chinese leaders were grotesque). It was okay because it happened at the end of game life-cycle. We have those things in civ7 from the beginning (and more).
Gameplay for last.
Loyalty introduced for fan-service reasons (people crying about forward settle) leads to circucal blob empires, players can't really have cool shapes like settling just coast, etc.. Obviously AI can't handle it.
Districts, ultimate noob traps, leads to the biggest tech gaps recorded in series for otherwise "alive" players. AI just can't handle it. Thankfully after only a single failed iteration we have a solution in civ7 (we had to dethrone science to allow yield specialization, who would guess?).
Districts also have an ugly cost formula. It is less fun than civ5 global happiness, however it is "hidden" therefore not many people hate it.
No anti-snowball mechanism. Initial archer rush = ahead in cities, territory, production, science, -5 diplo favour. Game is over.
City strength's formula. Baiting opponent into war just to buy a single Man-at-arms which almost triples the city's defense...
Oceans, navy... those are kind of redundant in civ6, aren't they?
Gameplay, balance, wonders, and even map scripts. I will have to finish it another day. To summarize, a game of 1000s mistakes, lack of strong lead which would forge it into the game that stand the test of time.