Any motivation to join the goblins?

I’m playing the game for the first time and just defeated the goblins. I talked to Minartha who tried to get me to attack the grove but I don’t understand why anyone would do that?

Halsin is supposedly the guy with answers. your whole motivation at this point is to get the tadpoles out of your head. The absolute/goblins don’t seem to offer any promise of doing that. Even if you are playing an evil character, you are still incentivized to side with halsin.

So strictly from a role playing perspective is there any reason why even an evil character would side with the goblins? Assuming they are making decisions with a goal of removing the tadpoles. Did I miss something?