Blog

“Rube’s Cube”- Out of the box D&D Encounters #11

Out of the box D&D Encounters Introduction:

Sometimes an encounter occurs because fo a single “what if”. It can lead in all sorts of unexpected directions. Imagine an illusionist’s castle, dungeon, or other lair. Imagine an environment filed with puzzles, tricks, and other dangers. Within such a confine, “Rube’s Cube” can exist.
For this encounter, I wanted to use an under-apprecited monster (ooze) in a way other than a hit point sponge or ambush predator. What followed was a series of “what if” questions.
What if a normally non-spellcasting creature had access to a spell or spell-like effect? In this case, I thought of Mirror Image.
No item to my knowledge creates such an effect outside of a ring of spell storing with the correct spell, so a little extra creativity was called for. What if you made such an item? In the end, you take what would normally be an ambush predator who may not survive more than three rounds, and you’ve created a mystical shell game with one ooze and one item. What if you take that creature, and that magic item, and place them in a room that is custom made for both in a fun way? Hmmm…
And so “Rube’s Cube” was born.

Environment: Dungeon
Suggested level: 2-3

Deep within a wizard’s lair, the party will eventually enter what looks like a simple room, 40’x40’, with a low 10’ ceiling. The door they will enter will be in the center of one wall, with an identical door on the far side on the opposite wall. What looks like a translucent square pillar suspends the ceiling in the very center of the room. It glows very faintly from within.
Once the party is fully in the room, the door will slam shut and lock. Consider it to be under the Arcane Lock spell with a DC 20 to unlock/break open.
Once the door is locked, the floor will appear to light up in primary colors, with each 10’ square in a shifting and changing primary color. If no other light source has been in the room to this point, this shifting light source will easily light the room in a rainbow of changing colors. It might be distracting, but is not harmful in any way.A Magic Mouth will appear on the far door and begin singing whatever dance music the DM desires.
Once this light show begins, the pillar in the center of the room will leave it’s suspended animation and begin to move.

The Gelatinous Cube is now active. Remember that the Cub has Blindsight, so any character or creature within range cannot hide from it by means of Invisibility. The Cube’s internal “survival instinct” will activate the object glowing faintly within it – the Ring of Mirror Image. (see “Treasure” below). The Gelatinous Cub will expend 1 charge to cast Mirror Image on itself. Now, instead of one Gelatinous Cube lit from below by brightly shifting primary colour, there will appear to be 4. Only one is real, and the rest are obviously illusions.
Trapped in a 40’ square room, there will now be a shifting shell game of Cubes. Fortunately, the Gelatinous Cube has a low Armor Class, so it should not take long to reduce the number of Mirror Images However, if the party outsmarts the number of images through some sort of area-of-effect spell (like Fireball, Lightning Bolt, and the like) or targets each of the separate images with a multiple-target effect like Magic Missile or Scorching Ray, simply have the Cube expend another charge from the ring. The Ring of Mirror Image has three charges.
In the meantime, the Cube will do what it normally does – advance slowly and try to consume the party.

Should the party defeat the Cube, both doors in the room will unlock, the floor will cease to light up, and a successful DC 12 Investigation roll will find the Ring among the remains of the Cube.

Monsters:

Gelatinous Cube (1)- As per Monster Manual, p. 242.

Treasure:

Ring of Mirror Images – Ring, rare (requires attunement) – While wearing this ring and attuned to it, the wearer may expend 1 charge to cast the Mirror Image on themself. (As per the spell, Player’s Handbook, page 260.). The ring has three charges minus any used during the encounter. It regains 1d3 charges at dawn.

Complications:

The obvious complication from this encounter is the Engulfing of a character by the Ooze. Should this occur while the Gelatinous Cube is under the effect of a Mirror Image, then the image of the Engulfed character will also appear inside any of the duplicate images of the Cube.
This has obvious dangers, but may have the hilarious side effect of creating an illusory “dance party” inside the brightly colored cubes. I would encourage any DM to try and pull off this effect, if only to break any tension and inject more humor into the encounter. You might even want to run the most obnoxious 70s Disco music during the length of this encounter as a background effect…and the players only get it to stop by killing the ooze.

Until Next Time, Stay Nerdy!