Taking on these guys requires AP ammo and rad-resistant gear right from the start, since their armor is seriously tough. Get yourself a high-penetration rifle with a suppressor, these work great against their patrols and you'll want the stealth advantage. The SEVA suit gives you solid protection against both radiation and anomalies, which is crucial when moving through their territory. Pack plenty of antiradiation meds, and keep your distance from those Psi-emitter towers, since they'll mess with your head and make you shoot your own team.

Good detector equipment helps spot their ambush points and psi interference zones before you walk into them. Watch out for their flanking moves, they coordinate like they share one brain sometimes. Grenades work great for breaking up groups, and always have a fallback position ready since they love trying to surround you. Keep moving, stay aware of radiation hotspots, and dont let them pin you down in one spot too long.