foam fractionation

foam dissipates a bit faster, has less ammo, and does 60% more damage per second
tech: foam fractionation - foam is 100% bigger when you are below 200 ammo

difficulty now increases linearly, even after beating the final boss

js/spawn.js

@@ -102,7 +102,7 @@ const spawn = {
             level.exit.x = 5500;
             level.exit.y = -330;
             //ramp up damage
-            for (let i = 0; i < 4; i++) level.difficultyIncrease(simulation.difficultyMode)
+            for (let i = 0; i < 2; i++) level.difficultyIncrease(simulation.difficultyMode)
 
 
             //pull in particles