Its not the best idea to attack them with swarms of little guys like the dilos or dimorphs. They have wide attacks, deal alot of damage, and take a beating. I lost my whole squad to one. But I found out that they can easily be killed by a baryonyx if you lure it to the water where the Bary can use its stun attack. After its stunned just stab it with a pike and use the stun attack whenever it snaps out of it.