Unfortunately I ran out of time before getting enemy AI into a workable state (and interactions between the player and enemies), so for now enemies don’t appear naturally.
If I continue working on this after the jam, I’ll aim to have a few type / factions of enemies that appear in clusters around the map. Factions would have basic AI with different dispositions; passive clusters that defend their own territory, active clusters that act like a player and grow, or aggressive clusters that seek out and attack the player.
(In theory this could also be generalized to make this a multiplayer game, with a lot more work.)