- SLIPPERY SLOPE
Stench. A rotting stench fills this 30-foot-high cavern.
Slimy Corpses. The slime-coated floor slopes toward
an underground river. Lying in the slime are the putrid
corpses of three kuo-toa and four troglodytes.
Aboleth Projection. As the characters make their way
along the tunnel leading west, an aboleth crawls out
of the water and confronts them. This aboleth is a
magical projection created by Illuun to intimidate the
characters.
Illuun the aboleth can sense the characters' presence
and creates a magical projection of itself to interact with
them. The projection lasts for as long as the aboleth
maintains concentration, as if concentrating on a spell.
Although the projection is intangible, it looks, sounds,
and moves like the aboleth.
Illuun can sense, speak, and use telepathy from the
projection's position as if the aboleth were present at
that location. If the projection takes any damage, it dis-
appears. The aboleth has had unpleasant dealings with
adventurers in the past and maintains a healthy fear of
them. It uses the projection to warn characters that it
will not tolerate incursions into its domain and urges
them to withdraw or face extermination. It suggests the
characters take the south passage to the river, then fol-
low the current down to Wyllowwood (level 5). It's happy
to Jet them descend to lower levels of Undermountain,
for it plans to conquer those levels eventually itself.
If the characters seem adamant about pressing deeper
into the aboleth's lair, Illuun telepathically commands
the eighteen troglodytes in area 24 to circle around be-
hind the characters (using the passage that enters area
15 from the south) while it keeps the characters engaged
in conversation. At the same time, it calls the three
chuuls from area 16 to come at the characters from the
west, trapping them in the tunnel. As soon as the chuuls
and the troglodytes arrive and begin their attack, the
aboleth projection disappears.
- GROTTO OF MADNESS
llluun the aboleth has turned this flooded cavern into
a den. The cavern is also defended by three chuuls that
are under the aboleth's sway.
The water varies in depth from 20 to 50 feet, and the
cavern's domed ceiling is 30 feet higher than the water's
surface. The walls are coated with slime but have abun-
dant handholds. A successful DC 15 Strength (Athletics)
check is required to climb them.
16A. LOST ISLAND OF BULBA-SLOPP
Rising out of the water is a rocky island upon which the
kuo-toa raised a shrine to their old god:
Chuul. Circling the island's perimeter is a chuul that
attacks anyone who sets foot on the island.
Petrified Otyugb. In the middle of the island, wearing
a crude net as a cloak, is a petrified otyugh that the
kuo-toa adopted as a god and named Bulba-Slopp.
Treasure has been piled around the statue's three
stumpy legs.
Before the kuo-toa arrived, this island was inhabited
by an otyugh. Halaster turned it to stone and lured kuo-
toa to the grotto, knowing that the insane fish folk would
come to worship the petrified otyugh as a god. The
kuo-toa named it Bulba-Slopp, and it served as their god
until the aboleth came on the scene. After Bulba-Slopp
failed to protect the kuo-toa, the archpriest Noolgaloop
set out to craft a new god, and Bulba-Slopp was wor-
shiped no more.
Treasure. Piled around the petrified otyugh's feet are
3, 300 cp, 670 sp, and 350 gp.
The net draped over the otyugh is woven with worth-
less shells and bones. Tied to the net are two trinkets
(roll twice on the Trinkets table in chapter 5 of the Play-
er's Handbook), a rusty gauntlet, a leather boot, and an
amulet made of composite wood and iron. The boot and
the amulet are both magical:
- The boot is one of two boots of elven kind. A single
boot is useless without its companion. The matching
boot was swept downriver and eventually found by a
goblin werebat named Vool (see level 5, area 17).
- The amulet controls the wandering shield guardian on
level 1 (see "Shield Guardian," page 14). A rune on
the back of the amulet matches a similar rune on the
construct.
16B. LAKE OF THE ABOLETH
Monsters. Illuun the aboleth and two chuuls lurk in
the water, which is dark, slimy, and fouled by the abo-
leth's presence.
Underwater Tunnel. A 10-foot-high, 20-foot-wide under-
water passage connects this cavern to area 16c.
The aboleth and the chuuls prefer to fight underwater.
In addition, the aboleth makes use of lair actions on this
level of the dungeon. Although the aboleth wants more
slaves, preserving its own life is more important. If its
chuul bodyguards are killed, the aboleth telepathically
summons the two chuuls from area 17 as it withdraws
to area 16c, where it makes its final stand.
The water in the northeastern half of the cave plunges
to a depth of 50 feet. As one travels toward the south-
west wall, the lake's depth shrinks to 20 feet.
16c. TREASURE TROVE
An underwater passage leads to this 30-foot-high cave.
The water here is slimy and fouled by the aboleth's pres-
ence, and every surface of the cave is covered in slime.
A kuo-toa whip and two kuo-toa stand guard atop
a pebbled beach strewn with dead crabs, rotting fish,
and treasure. These kuo-toa have been magically
enslaved by the aboleth. While enslaved, the kuo-toa
remain in constant telepathic contact with the aboleth,
but they can't take reactions. Whenever an e nslaved
kuo-toa takes damage, it can make a DC 14 Wisdom
