stachnie
Theorist
The costs of units, particularly mid-game range ones like the ones you mention, have long been extremely under-set for game balance.[...] So as units are being reviewed, you'll see some of them appear to be very expensive.
O.K., thanks. As for 1 HP City Guards: I was able to merge 3 of them, got a STR 5 unit (100 HP?) but I was unable to split it back. However, disbanding all 1 HP units led to a dramatic Crime increase, so I abandoned these experiments and loaded a previous save...
And yes, there are some serious balance issues in SM. If I have a few Bandit Riders merged once especially with a Quality Up promo, they may entirely wipe strong late Ancient civs (my civ is at the beginning of the Classical era now). I reduced the strongest rival civ - 12 cities - to 3 and stopped that, because I did not want to wipe them (I have ordered Riders to just autopillage). And this is on Immortal. Maybe game speed also matters, because I like to play at Eternity. At Emperor and Pangea, I was able to wipe all opponents (IIRC 10 or 11 civs) in the Prehistoric era (I had 5 or 6 groups of once merged STR 3 units and I lost only one of them).
S.