It's defending a city being attacked. It'll move its present archer one tile to the right of the city, rather than inside it, probably because another unit is slated to arrive in the city(but is 2 turn away). Your 3 archers 1 shot it in one turn. Never gets off a volley. Slated archer arrives, but uses 2/2 MP and ends its turn... 1 tile outside the city. Move your 3 archers up, 1 shot it in 1 turn. No volley launched.
4 warriors show up. Engage. Can only surround your triangle 3 places. 4 is a forest/hill. You shoot the 2 warriors that move up in the briefest way, and one falls, on approach. The 3rd is taking an extra long way to get around the other two and the 4th is behind forest/hill. End turn. Shoot the 2nd warrior, down, end turn. Take an attack from the 3rd long way warrior. Shoot it, rotate. Take an attack from the warrior that's used 2 turns from taking the forest hill. Shoot it down after another rotation.
In the end, you've taken 3 attacks, launched 18(!!!!!), defeated a force twice your size, and taking the city is a done deal. And this is routine as can be.
Nice description of the incompetence of the AI with the 1UPT system.
This 1UPT system is used in pure war games, with many differences:
- Everything is pre-placed, where the AI is given a highly advantageous position.
- The maps are mostly empty of units. Most tiles don't have a unit, making it far easier to move units relative to each other, with less blocking
- The movement speeds are far far higher, making it far easier to move units relative to each other, with less blocking.
- It is the only focus of these games, so they can build the terrain features around this combat.
- It is the only focus of these games, so they can work on building a decent AI for this form if warfare.
And even then, you typically fight against an army twice your size controlled by the AI and you barely lose units in the battle.
So forcing such a system on civilization with much denser units on the map and far lower movement speed is doomed to result in an AI incapable of forming a challenge in warfare.
Luckily many combat systems have already been developed around limited units per tile which offer a more interesting warfare, where the composition of your stack, the combined arms effects, the fact that some units are the counter to other units, are all taken into account.