Image: Bend Studio / PlayStationNo screenshot of NERO Injector: Health yet. This one shows NERO Checkpoints (Bend Studio / PlayStation).
A Health NERO Injector permanently raises Deacon's maximum Health. Injectors come from NERO checkpoints and research sites, and Health is the safest stat to raise first.
Yes. More Health helps in every fight, on every difficulty.
Put all injectors into one stat if you want Performance Enhanced sooner. Many players pick Health first.