D&D 5E Greater Invisibility and Flanking?

[aco175]

Had a situation come up last night with a PC using greater invisibility attacking a monster. Another PC came over to attack the same monster and wanted to flank. My first thought was that the second PC could not see the first PC, so no flanking bonus. A player argued that the monster is distracted by the first player attacking him, so it should not matter. I can kind of see both reasons, more so since invisibility is not as powerful as older editions and monsters know which square you are in unless you have silence as well. Just wanted to get thoughts.

 

[Mannahnin]

I don't think there's any exception for invisible attackers.

The 5E flanking optional rule does require the attackers to see the TARGET to flank them.

 

[Swarmkeeper]

I don't use the flanking rules any more for... reasons... but, for your scenario, I'd say the flanking bonus applies after the invisible PC has revealed themself in some way, which I think is a fairly trivial task in 5e. An attack would certainly do it. And, to your point, if the PC is not trying to be silent, the monster would most likely now be alert to their presence per the Hiding guidance that, in combat, most creatures stay alert for signs of danger all around (PHB p 177).

Now, does the ally know exactly where their friend is so they can align themself for the flanking bonus? Probably...

 

[Oofta]

Just because you are invisible, it doesn't mean that someone knows approximately where you are. You need to make a successful stealth check to be hidden from an enemy, that typically requires a hide action (bonus action for a rogue). So the target knows there's someone there and they are being flanked.

I might make an exception the first round before the invisible character attacks because they may not notice something they can't see approaching in the heat of combat.

 

[nevin]

Had a situation come up last night with a PC using greater invisibility attacking a monster. Another PC came over to attack the same monster and wanted to flank. My first thought was that the second PC could not see the first PC, so no flanking bonus. A player argued that the monster is distracted by the first player attacking him, so it should not matter. I can kind of see both reasons, more so since invisibility is not as powerful as older editions and monsters know which square you are in unless you have silence as well. Just wanted to get thoughts.

If the invisible player is physically affecting the target and meets the flanking rules I'd allow it. The attacked player would be reacting to whatever was physically affecting them. (including any illusionary or other mental effects). the point of flanking is with two or more attackers they are harder to deal with so I'd say yes. Now if the invisible creature was in place and had done nothing to noticeably affect the target I'd say no because the first attacker would get no break from any distraction.

 

[Stormonu]

I think we've had a thread similar to this before.

If both the invisible and visible PC are attacking, I'd give the flanking bonus; the difficulty is in protecting from attacks from both directions, seen or unseen.

 

[ad_hoc]

It comes down to your purpose for using the flanking rules.

Personally seems rather silly that 2 visible PCs would both get advantage but if 1 was invisible it would actually be a detriment.

In a game with flanking greater invisibility loses a lot of its power.

 

[Voadam]

The rationale is generally that a target defends themselves at least minimally when facing an opponent and the target when facing two foes on opposite sides has to position themselves disadvantageously compared to when fighting just one front.

Having one of those foes be invisible would be even harder to try to protect yourself so it would be easier for either attacking foe to pick up on the target's disadvantage.

 

[Voadam]

I don't think there's any exception for invisible attackers.

The 5E flanking optional rule does require the attackers to see the TARGET to flank them.

That's my RAW reading too.

DMG page 251:

"A creature can't flank an enemy that it can't see. A creature also can't flank while it is incapacitated. A Large or larger creature is flanking as long as at least one square or hex of its space qualifies for flanking."

 

[jmartkdr2]

If you need to change the explanation, the invisible character is effectively hidden because the enemy is focused on the visible ally, and the visible ally is able to take advantage of the distraction caused by the invisible ally attacking.

Although I'm still not sure I'd allow the visible ally to get the benefit even if I allowed flanking. It is easier to hide form someone who's trying to block axe-swings form someone else.