Difficulty 1 through Difficulty 3 reduces enemy spawn rate
Difficulty 1 through Difficulty 5 reduces enemy blood/damage
For Elite monsters that swipe while wounded, limit their maximum number of simultaneous presence to 2 to improve the stability of the gun school in Endless Mode
Probability optimization
Add pre-requisites to some components/technologies to avoid refreshing them in the store when they are not needed for the current playthrough
Avoid frequent reappearance of unneeded components/technologies:
If you skip buying a component, the next 10 components that appear in the store will all be different (unless there are less than 10 components available).
If you skip buying a tech, the next 25 techs that appear in the store will be different (unless there are less than 25 techs available)
Technology intensity adjustment
Excessive Refresh: Reduce the number of refreshes required, need 4=>3 refreshes to get a refresh discount
Super Refresh: Reduce the number of refreshes required, need 5=>4 refreshes to get attribute enhancement
Super Armor: Increase the permanent damage increase benefit of uninjured damage in this wave, +3% damage increase => 5% damage increase
Death Rocket: Reduce the size of Death Rocket, but increase the damage of it, every time you trigger the firearm component, increase the size by 3%=>2%, increase the damage by 6%=>15%.