Some affix have higher dmg after attack X number of monsters, or when moving, etc… Maybe your rogue have it and your wizz don’t.
Yes, I think you are right, I use adventurer and plagued on my rogue and not on my wizard.
I think you have found resolute about your 2nd concern so, I’m here to explain about the first. In Malum Boss there is a particular place where he permanently appears and stands after strolling around, if you’re lucky to have a ground based spells (meteor, smash, storm, earthshatter, etc) you would likely damage him when you cast the spell on the spot . Twister is a ground-based spell and has an AoE (Area of Effect) damage so basically when it touches the ground where the Worm regularly spawns it deals damage. That explains it.
Thank you for explanation, but is this considered a bug or a feature? In all the other games I played you could deal damage to a boss only when you hit him directly, not when you hit him where he is not right now. Unless Malum is considered an electron-like wave entity, he should be only on one spot at one time Or if we imagine he digs a hole in the ground, your spells then go through this hole all the way to him