| Biters have 15, 75, 375 and 3000 health (small, medium, big, behemoth) and spitters 10, 50, 200 and 1500; a spawner starts at 350, and its health grows with evolution up to tenfold. | Spawners | Code |
| A spawner keeps up to 7 units of its own and spawns one every 6 seconds at evolution 0, quickening to every 2.5 seconds at evolution 1. | Evolution | Code |
| The three sources add into a total that is squashed into the range 0 to 1 as total / (1 + total), so each gain is cut by (1 − evolution)² and evolution never reaches 1. The pollution that counts is what machines produce, not what spreads, so trees and terrain don't slow it. | Advanced: Evolution factor components and computationAdvanced: Evolution factor components and computationAdvanced: Evolution factor components and computation | Wiki |
| Enemies expand: between 10 and 60 minutes apart, shorter as evolution rises (60 minutes at evolution 0, 10 at 1, on the curve −e² + 2e), a group of 5 to 10 units times 8 to the power of evolution (so 40 to 80 at evolution 1, at the default enemy base settings; 2.1 also scales it with the map's base-size setting) sets out to a chunk 3 to 5 chunks out from the enemy bases already there, where its members turn into new spawners and worms, one every 30 seconds. | Expansion | Code |