by Mike Shea on 15 September 2014
At Gencon 2014 the Wizards of the Coast R&D team discussed tricks to the Dungeons and Draogns 5th Edition rules that DMs and players might forget at their (or the poor monsters') peril. Many of us are familiar with various versions of D&D and it can be easy for us to get right into the game without realizing that there are a few subtleties in 5e that we haven't seen in other games.
Today we're going to look at a few of these subtle 5e changes so both players and DMs might better remember them at the table.
Previous versions of D&D let spellcasters cast multiple spells with ongoing durations. At higher levels this led to casters firing off piles of buffs before they entered tough battles.
In D&D 5e, many ongoing spells require "concentration". Each character can only keep one concentration spell up at a time. We might think of it as though each character has an empty concentration spell slot. When any concentration spell is cast, it fills that slot. If they cast another concentration spell, the new spell pushes the old spell out of the slot. This prevents a single PC from casting multiple concentration spells at a time and reduces the amount of concurrent ongoing spells considerably.
If a player doesn't understand concentration, they could easily think they can cast a bunch of spells and keep them all going at the same time. You can identify concentration spells by the label of "concentration" in the spell's duration.
Of all the new features of D&D 5e, the concept of "advantage" is likely the most popular. In short, when you have "advantage" you can roll 2d20 instead of a single d20 roll and take the better of the two rolls. On the flip side if you have disadvantage you roll 2d20 and take the worse result.
The gotcha with advantage is that it doesn't stack. Having advantage from multiple sources is no different than having it from only one. Even if you have it from five different sources, you still only roll 2d20 and take the better.
Of course, the same is true with disadvantage. If you're prone, poisoned, and blinded, you still only have disadvantage once and still only roll 2d20 and take the lesser result on an attack roll.
It's easy to understand that having both advantage and disadvantage end up canceling each other out. But what if you have advantage from three sources and disadvantage from only one? The answer is simple if not entirely obvious. Any number of advantages mixed with any number of disadvantages cancels both. No matter how many sources you have that provide you advantage, if you're prone, you don't get to roll twice and take the better. Likewise, even if you're prone, poisoned, and blinded, if you're invisible you can attack without having to roll twice and take the lesser result.
There are lots of ways to gain a bonus action for certain things. Dual wielding, for example, lets you attack with your off-hand weapon as a bonus action. Bonus actions do not stack, however. Each character can only take one bonus action in a round. Even if you have three ways to take a bonus action, you can only choose one of them to take in a round. For example, a rogue cannot attack with an off-hand weapon and take cunning action in the same turn.
It will be easy for players to forget that they only get one bonus action and may end up taking many extra bonus actions if it isn't clarified to them.
The same is true for reactions. "Reaction" actions can only be taken by each PC once per round. This is a big change for opportunity attacks of which PCs could take as many as triggered. In D&D 5e, opportunity attacks can only be taken once a round even if provoked by a pile of monsters. Of course, the same is true for monsters, even big ones, who can only take one opportunity attack per round no matter how many PCs dance around it.
Thanks to DM David for pointing out that there are no delayed actions in 5e. Players can skip a turn if they want. They can also take the ready an action as an action during their turn and then use their reaction to do whatever it is they readied if the trigger should occur. You can read all about this on page 72 of the D&D Basic Rules. Readying an action will not change the PCs place in initiative.
In regards to tactical combat, there are a few interesting rules we might miss. First, there is no flanking. Classes like the rogue get to backstab when a target is engaged with an ally but there is no +2 bonus when you're on opposite sides of a creature. This makes it that much easier to engage in narrative combat.
Second, allies provide partial cover to everyone. If you're shooting at something and anything is in the way, your target is +2 to defenses. This generally makes it a pain to shoot into a crowd.
Third, moving through allies counts as difficult terrain. This off-sets the ability to split movement with an action. It also prevents PCs in the back from moving through allies, attacking, and then moving back again.
As we dig into this new edition of D&D, we're likely to find other gotchas that trip us up when we're playing the game. Expect to find this article article updated as we all learn more about the game. In the mean time, keep on rolling those 20s!