Guess how I found out there was a 105 Tusoteuthis in the water with me....

Don't hit them. Just... dont't

Ammonite is passive, and when you hit it, you (or your mounted tame) will get the Buff/Debuff "Rage" (depending how you look at it)

With the Buff/Debuff, everything nearby will have a sudden, uncontrollable urge to kill you. Even the Parasaurs!

You can find Ammonite dwelling in the deep ocean, usually alone or in groups of 1-3. They are untameable. They drop Ammonite Bile, used to craft Pheromone Darts. If you get hit with "Rage", Prepare for that Alpha Mosasaur you thought you had outrun or that Tuso to come out and slaughter you. Or just get offed by a Coelacanth. Both is good.

More Ammonite Encountering Tips