I'm working with the 5e basic rule set and have run into some questions about Arcane focus. I can't find where it is described, but from these forums I gather that wielding your focus allows for your proficiency bonus to be added to you spell attack roll. So d20 + ability mod + proficiency (when wielding arcane focus).
Does the proficiency damage also apply to spells? As in does Magic Missile do d4 + 1 + proficiency bonus? I know that it doesn't say it does, but I want to make sure I'm not missing something.
Does the arcane focus replace the need for components? Just got confused when you can choose an arcane focus or a component bag.
2a (bonus question) Does a component bag replace the need for components, or is it just a useful place to store them? If so, why not just store them in a pocket? What other bonuses does it grant?