MechaTarrasque
Hero
The D&D website has a new Sage Advice column: http://dnd.wizards.com/articles/features/rules-answers-september-2016
Highlights:
Bards can retrain magic secrets, but only with bard spells.
Rogues don't get any special benefits from hanging out with people with polearm mastery--it's not the size of your polearm, it is the 5 feet in the sneak attack rule. Familiars do count as allies for purposes of rogue abilities.
Dealing damage doesn't stop the target's movement, unless the way you did damage does (or you took the sentinel feat)
Conjured animals don't automatically count as magical for purposes of overcoming resistance/immunity. Demons laugh at your conjured pack of wolves.
Highlights:
Bards can retrain magic secrets, but only with bard spells.
Rogues don't get any special benefits from hanging out with people with polearm mastery--it's not the size of your polearm, it is the 5 feet in the sneak attack rule. Familiars do count as allies for purposes of rogue abilities.
Dealing damage doesn't stop the target's movement, unless the way you did damage does (or you took the sentinel feat)
Conjured animals don't automatically count as magical for purposes of overcoming resistance/immunity. Demons laugh at your conjured pack of wolves.