2

Roll 3d6 Kuo-toa and Roll 1d4 Kuo-toa Whips lead by an Archpriest

3

Roll 2d6 Wights or Gargoyles

4

Roll 2d4 Hook Horrors

5

1 Aboleth with Roll 2d4 Kuo-toa

6

Roll 1d4 Salamanders

7

Roll 1d4+2 Quaggoths led by a Quaggoth Thonot

8

Roll 1d4+1 Chuuls

9

Roll 1d4 Umber Hulks

10

Roll 1d2 Ropers with Roll 2d4 Piercers

11

Roll on "Underdark Low" (lower-level encounter)

12

Roll 1d3 Stone Giants or Earth Elementals

13

1 Drow Mage with Roll 2d6 Drow

14

Roll 1d2 Mind Flayers and Roll 2d6 Quaggoths

15

Roll 2d4 Phase Spiders or Hell Hounds

16

Roll 1d4+2 Gricks led by a Grick Alpha

17

Roll 1d3 Driders with Roll 2d6 Giant Spiders

18

Roll 1d4 Beholder Zombies

19

Roll 1d4 Vampire Spawn or Xorns

20

1 Spirit Naga