When about three spawn, one will turn into a alpha, ( large and orange) which are the ones that drop the venom. WARNING: When they drop the venom, a bag will drop with the venom inside, it won’t go into your or your tames inventory!!! If ten spawn, a reaper will appear. Keep a light pet with you so they don’t overwhelm you. Light pets will burn them, doing major damage. That’s really all you need to know to fight them!
Be very, very careful when venturing in their territory, for if to many spawn you will be completely overwhelmed. If you have a team of tek tier players you could farm the big orange ones and get their venom ( if you can get down and back up alive)
WARNING: Never use rock drakes against them!!!!