Factorio Version Required
0.16 is required because in 0.17 biters are still affected by belts, but it doesn't completely bug them anymore
How it worked

Defence Potential
- Under testings conditions described below this setup can deal with 200 mixed behemoths horde several times without taking damage. All natives dead.
- Offcourse this defence is not impenetrable. 200+ behemoths could damage belts or turrets sometimes. Use robots to mitigate the risk (robots can be damaged too).
Testing conditions:
- unlocked Laser turret shooting speed 7
- unlocked Laser turret damage 7
Requirements
- Lazer turrets consume up to ~20 MW with no tech bonuses and up to 60 MW with Laser turret shooting speed 7
- NB! do not use flamethrower turrets because they damage belts
Links:
- This blueprint is derived from this one
