Engage Onycs from a distance whenever possible, since attacking them makes them close in quickly and swarms can overwhelm you or push you into hazards. Use bug repellent to help avoid detection, keep your back against a wall in dangerous caves, and bring strong armor, healing brews, and an antidote or Wyvern Milk in case of Mega Rabies. Reserve melee weapons for emergencies and avoid grouping closely with infected survivors.