This is a fork of Ralnoc's mod Reactive Evolution Factor. Amazing mod, highly recommend if you play space age.

This drops requirements for space age (this means loss of functionality for Gelba), and sets Events Logger as optional. Adds support for evolution reduction when killing units.

Console commands you can use to verify it is working:
-- Spawn a biter-spawner near you
/c game.player.surface.create_entity{name="biter-spawner", position=game.player.position, force="enemy"}

-- Spawn a spitter-spawner
/c game.player.surface.create_entity{name="spitter-spawner", position=game.player.position, force="enemy"}

-- Spawn worm turrets
/c game.player.surface.create_entity{name="small-worm-turret", position=game.player.position, force="enemy"}
/c game.player.surface.create_entity{name="behemoth-worm-turret", position=game.player.position, force="enemy"}

-- Kill all enemy entities on the surface (nuclear option, use carefully)
/c for _, e in pairs(game.player.surface.find_entities_filtered{force="enemy"}) do e.die() end

-- Read current evolution on your surface
/c game.print(game.forces.enemy.get_evolution_factor(game.player.surface))

-- Set evolution to a specific value for testing
/c game.forces.enemy.set_evolution_factor(0.5, game.player.surface)

-- Set it high so you have room to see reductions
/c game.forces.enemy.set_evolution_factor(0.8, game.player.surface)