diff --git a/Mage.Sets/src/mage/cards/u/UnderwaterTunnelSlimyAquarium.java b/Mage.Sets/src/mage/cards/u/UnderwaterTunnelSlimyAquarium.java
new file mode 100644
index 00000000000..01ee31db64f
--- /dev/null
+++ b/Mage.Sets/src/mage/cards/u/UnderwaterTunnelSlimyAquarium.java
@@ -0,0 +1,70 @@
+package mage.cards.u;
+
+import mage.abilities.Ability;
+import mage.abilities.common.UnlockThisDoorTriggeredAbility;
+import mage.abilities.effects.OneShotEffect;
+import mage.abilities.effects.keyword.ManifestDreadEffect;
+import mage.abilities.effects.keyword.SurveilEffect;
+import mage.cards.CardSetInfo;
+import mage.cards.RoomCard;
+import mage.constants.CardType;
+import mage.constants.Outcome;
+import mage.counters.CounterType;
+import mage.game.Game;
+import mage.game.permanent.Permanent;
+import mage.players.Player;
+
+import java.util.UUID;
+
+/**
+ * @author TheElk801
+ */
+public final class UnderwaterTunnelSlimyAquarium extends RoomCard {
+    public UnderwaterTunnelSlimyAquarium(UUID ownerId, CardSetInfo setInfo) {
+        super(ownerId, setInfo, new CardType[]{CardType.ENCHANTMENT}, "{U}", "{3}{U}");
+
+        // Underwater Tunnel
+        // When you unlock this door, surveil 2.
+        this.getLeftHalfCard().addAbility(new UnlockThisDoorTriggeredAbility(new SurveilEffect(2), false, true));
+
+        // Slimy Aquarium
+        // When you unlock this door, manifest dread, then put a +1/+1 counter on that creature.
+        this.getRightHalfCard().addAbility(new UnlockThisDoorTriggeredAbility(new SlimyAquariumEffect(), false, false));
+    }
+
+    private UnderwaterTunnelSlimyAquarium(final UnderwaterTunnelSlimyAquarium card) {
+        super(card);
+    }
+
+    @Override
+    public UnderwaterTunnelSlimyAquarium copy() {
+        return new UnderwaterTunnelSlimyAquarium(this);
+    }
+}
+
+class SlimyAquariumEffect extends OneShotEffect {
+
+    SlimyAquariumEffect() {
+        super(Outcome.Benefit);
+        staticText = "manifest dread, then put a +1/+1 counter on that creature";
+    }
+
+    private SlimyAquariumEffect(final SlimyAquariumEffect effect) {
+        super(effect);
+    }
+
+    @Override
+    public SlimyAquariumEffect copy() {
+        return new SlimyAquariumEffect(this);
+    }
+
+    @Override
+    public boolean apply(Game game, Ability source) {
+        Player player = game.getPlayer(source.getControllerId());
+        if (player == null) {
+            return false;
+        }
+        Permanent permanent = ManifestDreadEffect.doManifestDread(player, source, game);
+        return permanent != null && permanent.addCounters(CounterType.P1P1.createInstance(), source, game);
+    }
+}
diff --git a/Mage.Sets/src/mage/sets/DuskmournHouseOfHorror.java b/Mage.Sets/src/mage/sets/DuskmournHouseOfHorror.java
index 2ff090465b4..41d3234fd76 100644
--- a/Mage.Sets/src/mage/sets/DuskmournHouseOfHorror.java
+++ b/Mage.Sets/src/mage/sets/DuskmournHouseOfHorror.java
@@ -369,6 +369,7 @@ public final class DuskmournHouseOfHorror extends ExpansionSet {
         cards.add(new SetCardInfo("Undead Sprinter", 350, Rarity.RARE, mage.cards.u.UndeadSprinter.class, NON_FULL_USE_VARIOUS));
         cards.add(new SetCardInfo("Under the Skin", 203, Rarity.UNCOMMON, mage.cards.u.UnderTheSkin.class, NON_FULL_USE_VARIOUS));
         cards.add(new SetCardInfo("Under the Skin", 323, Rarity.UNCOMMON, mage.cards.u.UnderTheSkin.class, NON_FULL_USE_VARIOUS));
+        cards.add(new SetCardInfo("Underwater Tunnel // Slimy Aquarium", 79, Rarity.COMMON, mage.cards.u.UnderwaterTunnelSlimyAquarium.class));
         cards.add(new SetCardInfo("Unholy Annex // Ritual Chamber", 118, Rarity.RARE, mage.cards.u.UnholyAnnexRitualChamber.class, NON_FULL_USE_VARIOUS));
         cards.add(new SetCardInfo("Unholy Annex // Ritual Chamber", 339, Rarity.RARE, mage.cards.u.UnholyAnnexRitualChamber.class, NON_FULL_USE_VARIOUS));
         cards.add(new SetCardInfo("Unidentified Hovership", 305, Rarity.RARE, mage.cards.u.UnidentifiedHovership.class, NON_FULL_USE_VARIOUS));