Close! You pick six units from among four tiers. Tier 1, 2, 3, and defenses. Five units in each tier. Pick any six. Theoretically, you could pick all five defenses and try to turtle. And, yeah, it’s swarming of a sort, but a lot of it is positioning, territory, attrition, countering units, scouting, regrouping, and – if you’re really hardcore – managing individual units types. Left click for “all attack here”, right click for “selected unit type attacks here”, and hold down the button to command units to follow you (i.e. retreat).
Also, the economy is super finicky, which is a substantial part of the gameplay. In a way, it’s like Total Annihilation in that you queue up stuff and have to manage the flow, but with very limited resources. If you don’t know what you’re doing, your army will starve to death.
I love it to pieces, but it’s a very peculiar beast. Which is a compliment!