We are playing the campaign path The Second Darkness and my friend is a druid with a ankylosaurus animal companion. We are all 7th level and he is doing way less damage than everyone else, which isn't saying much as we have a two weapon fighter (with two kukris, he hasn't seen the Saw-tooth saber/bastard sword or the Katana/Wakizashi combos) a paladin with 23 AC and a tendency to not tank damage, the druid that this is all about, a fire sorcerer (who is forced to fight hellhounds and fire elementals) and then finally me, a gunslinger a level below everyone else and banned from using advanced firearms and can't afford alchemical cartridges.
My friend does not want to change animal companion or class, but wants more damage. So are there ways to maximize the damage of the animal (e.g. can it use magic items and if so, what slots does it have).
He also wants some better spells. So what are the best 3rd and 4th level spells for druids? what are good higher level spells to take?