The PHB says that a paladin who breaks his oath can become an Oathbreaker Paladin or “abandon this class and adopt another.” Does this just mean begin mutliclassing as usual? Does a 10th level paladin who breaks his oath and switches to Fighter or Rogue retain all his existing Paladin powers and just become unable to learn new ones, or do some of them go away? I always had the impression that a fallen paladin (who does not become an evil paladin from the DMG) would lose his divine abilities temporarily or permanently.It’s based on the DM’s campaign. You can go two ways – the paladin can multiclass and keep the existing paladin powers, or the paladin rebuilds as a character with levels in a different class (most likely fighter).
In the first case, you’re saying that paladin is something that people can learn. As you level up in the class, you unlock secrets that you get to keep.
In the second, you’re saying that once you anger the gods, they take your power away.
In a campaign where paladins aren’t tied to deities, the first approach makes sense. The second one fits if you see the gods as tightly tied to what makes a paladin a paladin.Comment from discussion AMA: Mike Mearls, Co-Designer of D&D 5, Head of D&D R&D.

Comment from discussion Hi Mike!
Big fan. What’s the meanest/funniest thing you’ve done as a DM to a group of players? Not that anything DM’s do could be considered mean, they’re great. I unconditionally love them and would never want to upset them. All DM’s are powerful and good looking. Fact.
Also, what’s the meanest/funniest thing you’ve done as a player to another player or DM?
Meanest thing as a DM: It’s small, but it’s the first thing that comes to mind.
3e Eberron game, the characters are fighting their way through a frost giant outpost high in the mountains. The giants send a pack of dire wolves out to rush the PCs.
The halfling player comes up with a fiendish plan. He decides to leap on the back of a dire wolf and attack. The wolves can’t bite at him while he’s there, he declares. It would be crazy unrealistic for them to risk biting their packmate. Plus, the giants would clearly avoid throwing boulders at the halfling and risk squashing their pet.
I agree with his cogent points.
On the giants’ next turn, they use a free action to whistle and ready their actions to ends that are inscrutable to the players.
Halfling player is perplexed.
On the wolf’s next turn, it runs back to its master in response to the whistle.
Giant #1 pulls the halfling off the wolf’s back. Giants #2-6 pummel the crap out of him.
That was the last time he tried riding a giant wolf.
Funniest/meanest thing done to another player – buried a rogue alive, not realizing that the ring of regeneration he stole from the fighter was going to revive him in a few hours.AMA: Mike Mearls, Co-Designer of D&D 5, Head of D&D R&D.

Comment from discussion Hey Mike,
Just got into tabletop last year and now I’m addicted. Been following you ever since, lapping up the tidbits about D&D 5 leading up to the launch.
2 questions: 1. What’s your very best life advice? 2. What exactly does the D&D R&D office look like? I imagine there are vials and bunsen burners?Don’t just accept the options that other people give to you. Find your own path. If you don’t know what that path is, find a steady job to keep yourself comfortable while you work that out.
Focus on what you really want, not what people tell you you’re supposed to want.
People totally underrate jobs like becoming a plumber and look down their noses at it. But when you think about it, being a plumber pays well, you have different challenges every day, and when you get good you can start your own business with it. People will always need toilets and they will always pay lots of money to keep their toilets working.
And if your toilet breaks, you can fix it yourself.
The office is like your basic, open cube layout, but features a lot more D&D posters, action figures, board games, and dioramas of ruined castles than most other offices.AMA: Mike Mearls, Co-Designer of D&D 5, Head of D&D R&D.

I really don’t like doing a new edition. IMO, new editions of D&D would focus on cleaning up trouble spots, applying lessons learned in design, and sticking to the core elements that made a thing successful in the first place.
Basically, a new edition asks people to re-learn the game all over again. It has to be worth that effort.Will 5e dnd next be the final edition of dnd with continous support or will there be another edition in the future? Do you think it’s fair to fans/supporters to have so many editions?Comment from discussion AMA: Mike Mearls, Co-Designer of D&D 5, Head of D&D R&D.

CommentWhat are your personal processes for when you find you need to make up an encounter on the fly?I usually throw stuff at the players with CR in mind – if it’s something on the fly that’s just meant to be a quick fight, I use creatures with a CR at about half or less of the party’s level, no more than 3 – 5 critters. That usually seems to work. For a bigger monster, I just keep the CR at or less than the party’s level. from discussion D&D AMA with Mike Mearls and Chris Lindsay 1/15.

Comment from discussion [AMA] Mike Mearls, 5th Edition D&D Lead Designer.

Comment We wanted a premium product, especially in terms of art and book design, to ensure that the physical book had value as an object when compared to a future ebook. Obviously, that drove the cost up.
We also felt comfortable with that direction knowing we’d have a free version of the game available (Basic D&D).from discussion AMA: Mike Mearls, Co-Designer of D&D 5, Head of D&D R&D.