GURPS Gelatinous Cube (obstacle)

 Dungeon Fantastic: Iconic Monster Use & GURPS 10' Gelatin Cube Monster

 

Killer Cube O' Gelatin
A 10 foot cube of hunting gelatin. "Attacks" by moving into/onto a target and then digesting it. Usually motors along at less than 1 yard/second, eating mold, fungus, carrion, and wood (including doors in a pinch!), but it can and will speed up if attacked or it senses a large amount of food.

ST: 0 HP: 10 Speed: 4.00
DX: 6 Will: 10 Move: 2
IQ: 1 Per: 8
HT: 10 FP: 10 SM: +4

Dodge: N/A Parry: N/A DR: 0

Slam or Touch (N/A): 1 point corrosive damage (every 5 pts damage reduces DR by 1 and inflicts 1 damage) (doesn’t affect most metals or any stone/pottery) plus paralysis (contact agent, resisted by HT-2), lasts 1 minute after no longer in contact with cube.
Envelopment (N/A): It can fully envelop paralyzed foes; envelopment does 10 points of corrosive damage per second, plus paralysis as above.

Traits: Amphibious; Discriminatory Smell; Doesn’t Breathe; Doesn’t Sleep; High Pain Threshold; Immunity to Metabolic Hazards; Immunity to Mind Control; Injury Tolerance (Homogenous; No Blood); Invertebrate; No Legs (Slithers); No Manipulators; Regeneration (1 HP/Hour, not from fire); Silence 3; Universal Digestion; Vibration Sense (Air).
Skills: Stealth-12.
Class: Slime
Notes: Nonsentient and can’t negotiate. Plant/Slime spells won’t work. Gelatinous cube jelly is worth $10 a quart, 1d6 quarts can be gathered from a slain cube.

 

And from the comments section of that link:

• Wounded guys left behind, unconcious enemies left for "questioning later," corpses left for eventual resurrection - all have some real concerns with this thing. Armed and ready adventurers? None.
• Or deploy them by the dozens as support for the 10 x 10 x 10 yard Mother Cube that does 3d corrosive or so and has a boatload more HP. 
• An interesting variation on the cube would be to make it Diffuse, and make it a cloud of corrosive digestive vapor-slime instead. That would make it much harder to kill.
• Basically, it's a way to:
• explain why corpses, etc. disappear
• why chalk marks and such disappear from walls when your players ask why you didn't mention their chalk marks from eight sessions ago
• make it dangerous to leave wounded companions behind or leave corpses behind for later recovery and resurrection
• make it dangerous to let your guard down
• make a mobile obstacle, so previously "safe" places might not be safe this time. Or later on.
• make it dangerous to run in a dungeon, even to try and run out of the dungeon.

But it's not a foe any more than that 10' pit is.

I really like the idea of the cloud of corrosive vapor-slime. Harder to kill and likely faster moving. Maybe after sufficient meal it thickens out into a regular gelatinous cube and either remains stationary or slowly treks back to a "lair" to digest. It then returns to its vapor form before going on the hunt again.