If you hate Cnidaria as much as I do, get a raft and a blood stalker. Using the blood stalker to drag them out of the water is an instant kill, their webs will only reach to a certain depth however. So, either lure them to the top of the water or use a ranged weapon for any left over.

Use a Basilosaurus to kill you don’t get kicked off

Do NOT go near this creature, or at least have a ranged weapon

Be very careful near them I was cruising around with my Dino’s in the sea( a level91 bronto a rex a sarcophagus and a wyvern )I got onto my sarco and went under to get silica pearls and I see my bronco died so I got to surface thinking megladons then out of nowhere I get shocked then terror

Wyvern dead rex dead sarco dead bronto dead me DED

In ark mobile and you are a beginner you can shoot it with a bow and a stone arrow

They have a long agro range so be careful near them. They are also found at the surface a lot. I suggest to try to get to shore, then you can try to kill it. Try to get away quickly since there deadly.

OMG!! Some of these guys came up to my angler fish and started attacking it out of nowhere!! Then my Sarco Swam in and started attacking them!! I thought they would both be dead BUT THEY SURVIVED!!!!!

Kill these guys whatever chance you get with spears it’s pretty easy just don’t get stung too many times.

Recourse tip: these things drop bio toxin don’t get rid of it it has a good use of your too low a level to make narcotic (DONT EAT EAT IT it’s for creatures.)

When taking a creature if you want to bring up its torpidity to keep it asleep just feed it one of these toxins I collect them all the time. Just make sure you don’t feed the creature the toxin too early it could hurt it if you give it too much too soon. Feed it some once the torpidity is down at least halfway then feed it to the creature I always have these thing with me.

kill this fu***ng annoying jelly fish with bow or bait thia f**king annoying jelly fish to ground and use a pike(cause i hate normal spear,because spear can broke in 1 attack)

You can kill them if you go to the Shore and if they follow you just hit them with your axe or or something so you can you can you kill them I did it once cuz a drop spawned bright by 2 and I killed them afterwards when I got my stuff back and the drop

Rip fang and Mary who tried to follow me

I saw it happen as my lystrosaur swim down the river when she was attacked. I was shocked when she died. Then my moschops also swam and she died too

I lost my lystrosaur and mos chop to 2 Cnidaria

These jellyfish sting and are dangerous. They killed my first dinosaurs

once.

Have a crossbow in your hotbar AT ALL TIMES. Sometimes jellyfish will happen, and you must be ready

I think the killer jelly is a mix between a box jelly, deep sea jelly and a Man’oWar. The Man’oWar is not a jelly but like it and it’s sting almost burns you, the box jelly also would contribute to the sting and the deep sea jelly will get the glow. Lik if u think so

poke it with a spear and get it's very useful bio toxin.

I hate these guys they killed my friend and trike

Guys you gotta agree with me, These little blue jellyfish mfs are annoying

WARNING: while on my spino, I found some of these guys in shallow water. I decided to kill them for their bio toxin, and ran over with my powerful spino. It knocked me right off the saddle. Thank goodness it was shallow water. I swiftly killed these (I was level 96 with lots of melee upgraded). Also, they electrocute you while swimming, it makes you freeze in place, and then they kill you. Easiest way to kill: find some near shore. Swim out (only a little bit) wait for them to notice and start to come. Before they can reach you, swim back up to shore. They will be extremely close to shore, but make sure they’re close enough so you can still stand. Take a weapon (I used a pike) and stab them. Kill them, then harvest the, with your weapon, and enjoy the bio toxin. It’s literally all they drop.