Surprised it took me this long to think of this, but should two or more doppelgangers come into contact, would their detect thoughts abilities work on each other?
10\$\begingroup\$ I’ve just read through the stat block, and I feel like I’m missing something. I think if we had some more details about why you think it wouldn’t work, we’d have a better time addressing your confusion. \$\endgroup\$– Thomas MarkovMar 15 at 23:32
1\$\begingroup\$ Honestly, seems like it would be kind of necessary in a race of seamless shapeshifters that spend all their time in other people's forms. How're you going to find a mate without being able to figure out which people are in fact of your species? \$\endgroup\$– ShadowRangerMar 16 at 1:06
2\$\begingroup\$ @ShadowRanger- 5E doppelgangers don't mate with each other, they take on forms of and impregnate humanoids from other races, check your MM. \$\endgroup\$– king of panesMar 16 at 1:36
1\$\begingroup\$ is there anything in the stat block that suggests to you that it wouldn't work? If two wizards have detect thoughts, do you think they couldn't use it against each other? \$\endgroup\$– AnnaAGMar 16 at 9:10
There is nothing in the description of Doppelganger race that says that they are immune to 'detect thoughts' - in neither of three instances of Doppelganger race that I could find (Doppelgangers from Monster Manual, character secret from Icewind Dale, Dread Doppelganger from Minsc and Boo's Journal of Villainy). So, in case of two Doppelgangers meeting each other - one or both of them can read each other thoughts. Though, even such reading won't guarantee that they'd recognize each other as Doppelgangers, as their ability detects only surface thoughts and can't be used to probe deeper into mind.