AI needs to upgrade it's units!

[mazz0]

I remember reading a dev saying that corps were an attempt to to allow people ahead in the civics tree but behind in the tech tree to have a chance in fights. The AI should at least be forming corps and armies if they can't upgrade.

 

[Lord Shadow]

It seems like a perfect storm of factors like Strategic Resource availability, tech gaps, and maintenance/upgrade costs. Definitely in need of some tweaks, but I can imagine they'd have quite a big effect here. It's quite sad to see warriors floating around in the Renaissance and beyond.

Bingo. I concur. I don't think we'll get a solution for the tech gaps in the form of new units anytime soon (sounds like expansion material), but a temporary fix would be allowing upgrades to different sub-roles (i.e. Warrior -> Pikeman, Knight -> Cavalry). I'm fairly sure this was a possibility in previous Civs.

The other two factors could/should be addressed by patches in the short term.

On the subject of strategic resources, I'd always allow unit production, but provide two levels of strength maluses (say, -4 and -8) depending on whether the owner lacks one or two units of the resource in question. Otherwise it aggravates the tech gaps issue and leads to extreme situations such as the Warrior's, which in the absence of resources can't be upgraded at all literally until the advent of Infantry in the Modern Era. That's 80% of the game.

I remember reading a dev saying that corps were an attempt to to allow people ahead in the civics tree but behind in the tech tree to have a chance in fights. The AI should at least be forming corps and armies if they can't upgrade.

I've seen the AI do this. Despite being stuck with Swordsmen, Crossbowmen and Knights well into the Industrial Era, in my current game Cleopatra had produced lots of corps and the occasional army of those. Couldn't stop my Redcoats and Cavalry, but it's still a good idea from the conceptual standpoint. Especially for the AI, since it allows it to better concentrate forces in the absence of the old stack system.

 

[Elhoim]

The main problem is that the game forces you to upgrade to the latest version of the unit, and if you don't have the resource for it you can't upgrade to any of the intermediate "steps". For example, I had a war chariot and a knight (both heavy cavalry). I was in the modern era, and had just researched the technology that allows tanks. My war chariot was unable to upgrade to a knight, forcing me to upgrade directly to tanks, which I couldn't upgrade to as I had no oil. The game should allow upgrading to the "closest" unit.