They spawn in Genesis in several caves in the Lunar biome

It's a Giant crab that can throw it's enemies far away

Make sure to carry around grappling hooks
If picked you can graple the crab and it will let go

Kill and use chainsaw for organic polymer or even better use a moschops spec’d into organic farm to really increase that organic poly farm easily

Giant crab jumps super high, almost has a heart attack, the spawn in Lunar caves!

I killed one with just a bow and movement speed back up shoot turn around and run a little turn and shoot easy way to kill plus lots of chitin and organic polymer easy just bring enough ammo

In the wild crabs and spinos are buddies... they use the buddy system...

Unless I am missing something, the Quetzal CANNOT pick up the Karkinos with their feet.

They can walk over spiked walls.

It'll drop you if you log out.

Has a slow reaction time and you can usually avoid it attacking you by running under its legs.This might change in later patches

They often spawn near the lake by the portal in aberration so if your looking for one be careful and don’t swim to deep!

They drop Organic Polymer when you harvest their corpse

can be found along with ravagers and other creatures on Valguero. northeast of map, look for underground waterfall.

Can be used to tame aggres-passive dinos (e.g arthropluera) more easily by grabbing them since it doesn't drop them when you dismount like argentavis.

Throwing a plant z grenade can cause a Karkinos to drop you or your dino. Essential when traveling on Ravenger back.

Be careful when attacking them since then can grab you off of most mounts (including your own crab)

They seem to have a bug where a Sarco just stands under them so the can’t attack them somehow. I lost 2 craps to a lvl 10 sarco because of that.....

Beware of the front as they do a smash attack with their claws. They also have a pick up move which can pick up small dinos.

Then I told the police he grabbed me...