by Mike Shea on 11 June 2012
One of the more interesting mechanics from the D&D Next playtest is the handling of "advantage" and "disadvantage". In short, when a creature has advantage, that creature may roll twice on an attack and take the better result. When a creature has disadvantage, it must roll twice and take the worse result. The OnlineDM wrote a great article discussing the math of this mechanic called, Advantage and Disadvantage in D&D Next: The Math. My friend Bartoneus wrote another great analysis of the math behind advantage and disadvantage on Critical hits.
Note, my original summary of the math behind "advantage" and "disadvantage" was flawed, as pointed out by a few readers, so here is a better description:
Advantage and disadvantage have differing bonuses or penalties depending on the target number you're going for. Most of the time it's the equivalant to a +4 or +5 bonus except if the target number is really low or really high. Here's a quick summary table:
|Target Number||Comparable bonus or penalty|
|2 or 20||1|
|3 or 19||2|
|4-5 or 17-18||3|
|6-7 or 15-16||4|
One other note of consideration, advantage gives you two chances to roll a critical hit. If PCs already have a bonus to a critical hit, this further increases their chances. Likewise, having disadvantage makes it that much harder to roll a crit (down to 1 chance in 400).
The concept of advantage and disadvantage is a nice simple mechanic. It's a big bonus and it's easy to run at the table. Granting the best of two rolls won't slow down a battle, though forcing the worse of two rolls will.
While this mechanic lies deep in the roots of the D&D Next playtest, there's no reason we can't use it in our 4th edition D&D games. Today we'll look at using "advantage" and "disadvantage" as simple mechanics in our 4e games.
Combat advantage in 4e is very easy to acquire. For this reason, we don't want to simply replace CA with D&D Next's advantage mechanic. Instead, we'll use it for special circumstances such as environmental effects or as a replacement for 4e's more annoying status effects.
Take the high ground: If you have a large battleground and you want to get the PCs moving around, declare that certain areas higher up above the main battleground grant "advantage" to any creatures in that area firing down on those below. For example, a large field might have watchtowers that oversee the area. If a PC can make it up to a watchtower, that PC will be able to roll twice on any attacks hitting those in the main field. To make for a challenging battle, start some artillery creatures up in high-ground areas that grant them advantage against the PCs until the PCs get them out and, potentially, take over the position themselves.
Holy or unholy circles: Holy or unholy circles might grant advantage to a properly aligned creature. Good-aligned creatures in a holy circle might have advantage against non-good creatures. Unholy circles could grant the same for evil creatures.
The bloodlust battlefield: A bloodlust battlefield might let all creatures within it roll twice and take the better result. This will make for a very fast and swingy battle, but it could be a lot of nail-biting fun.
Grasping roots: While it always seems like a good idea to have grasping roots or other hindering terrain affect movement, in practice this can get annoying. It's hard to hinder movement without PCs getting too stuck. Instead, have creatures within hindering areas affected by "disadvantage". While in the hindering terrain, they must roll twice and take the worse result.
Mind fog: An enemy spellcaster might cast an area burst mind fog. Any creatures within the area must roll twice and take the worse result. Use this idea to get PCs out of a doorway if they tend to want to hang back and fight in a corner.
Advantage and disadvantage might give us a nice alternative to daze, stun, and weaken as well. For elites and solos, consider changing any daze, stun, or weaken effect to an effect that lets all PCs roll twice against the monster and take the better result. For example, if Brainy McWonderpants the Wizard dazes Flamebreeches the Red Dragon, instead of the dragon losing actions, all PCs may roll twice when attacking the dragon and take the better result.
A stun against a solo might include both advantage for the PCs and disadvantage for the solo. For example, if Chest Squatthrust the Barbarian stuns Flamebreeches the Red Dragon, Flamebreeches instead must roll twice for all attacks and take the worst result while all PCs may roll twice and take the better result.
It's worth keeping in mind that advantage will dramatically speed up combat by making many attacks hit while disadvantage will end up slowing it down as combatants miss much more often. You should also recognize that advantage doubles the chance of a critical hit, which, in 4e, can have explosive consequences at higher level. Don't give it out too often.
For a long time, we've considered a +2 bonus to be the DM's little helper. Want to reinforce good behavior or reward a cool idea? Give them a +2 bonus. Now, we have another more powerful helper as well. A DM can keep this mechanic handy and, whenever a situation warrants it, give the PC the best of two attack rolls for having an advantageous position or coming up with a cool adlib moment.