People claiming the otter is useless have never seen one go toe to toe with a megalodon and almost damn near win. It was on my shoulders when I died and it took me a while to find my stuff, but when I found it, the damn otter was still swimming around in circles, trying to beat up the massive shark that killed it's owner. It now has a tombstone made in loving memory.
So one day I went to the redwood river and I found and tamed one. 20 minutes later I was in the snow biome and a Chomp Chomp Giga came up and... well, CHOMP CHOMP... so I said “You will die for that” and it said “You should’ve gone for the head”
If you kill one, you will be hunted down by all the gigas and rexes and wyverns and everything deadly until you have started crying in real life from the regret of killing that little, innocent creature that just wanted a top hat.