Model of a Modern Major-General
Train all Units, across any number of playthrough.
Is it known what the precise requirements are for this achievement?
- Do you actually need to train all units, or is it sufficient to being gifted them by City States, or via promotion via Ancient Ruins? (like the Helicopter Gunship I acquired in a recent game :p)
- I would assume that paying for promotion of a unit counts as "training it" – Or do they need to be built new?
- Do you need to cover all country-specific unique units, or is the equivalent default unit sufficient? Eg, do you need to train a Janissary, a Musketeer and a Minutemen, or is just training Musketman sufficient?
I notice that 0% of users on Steam have this achievement, so it's possible that it's bugged. Update: 0.1% now have the achievement, so it's apparently achievable.
Best Answer
You need to build all the basic units, plus all the civilization Unique Units from the original release nations (no DLC). I'm sure the UUs are required as I popped mine on a Naresuan's Elephant.
It was a surprise to me, but the achievement logging has apparently been re-enabled at some point so you can check on your progress. Here's how (Hat tip to this CivFanatics forum post):
Interesting note, the Spaceship parts are also tracked in this log, but I'm not sure if they're required or not for the achievement.