Project Nemesis is a fan driven website for games that use the One-Roll Engine (like Nemesis, Wild Talents, Reign and Monsters) or Chaosium's Basic Roleplay System (BRP) (like Call of Cthulhu) and the Delta Green setting.
Agents who have terminated a Hummer have reported what happens if it dies. If killed, the Hummer congeals into a puddle of volitile chemicals and rapidly produces a cloud of noxious gases which can cause sickness or death in human victims. flourine, with traces of chlorine and ammonia can be found in this puddle.
Dissolution is not instantaneous, but rather gradual over a few minutes (the amount of potential harm starts quite low, reach a peak and tail off as the gas disperses). Anyone standing close enough (a few feet... most likely if they walk up to the dead interstellar abomination to take a good look at their handiwork) might get a lung-full and suffer some damage. Burning eyes and throat are the first symptoms, progressing on to itch and then burning of skin. At this point smart agents will take the hint and leave. People further away will be aware of noxious chemical odours. Bear in mind that anyone standing close to a _live_ Hummer is going to be in a lot more trouble than someone standing next to dead one!
In any case, agents should have time to remove themselves to a respectable distance before taking major damage. This may not be so easy if you waste the thing in a confined space.
Surrounding non-animate objects will be damaged by the Hummer breakdown products, but this damage is likely to be superficial rather than terminal. Small bodies of water (puddles, fishtanks etc.) will likely acidify from the chlorine and flourine which will dissolve readily in them. The vapour cloud will take a few minutes to disperse under conditions of still air, decreasing as airflow increases. Carpets and soft furnishings will suffer irreparable damage. Paint in the area may peel and discolour. Sidewalks, brick, mortar and asphalt might also suffer cosmetic damage. Trees, grass etc. will die soon.
Any agents stupid enough to stand there whilst something paranormal is happening deserves what they get.
Autopsy Report on preserved skin tissue/residue of a dead Hummer From the files of Professor Grant Emerson
The skin (or Hummer residue) is a dark viscous fluid, similar in aspect to bitumen. A closer visual inspection reveals it as an heterogeneous goo, with a surface of soft gloss property, varying irregularly. In a further stage of "decomposition/transformation", the Hummer corpse evaporates/sublimes, it clots, leaving as residue a bumpy shineless mass. (something as a self-saponification but not producing your average soap and glycerol) - Although also identified as a mixture of hydrocarbons, it has metallic traces and it is not fully soluble in carbon disulfide.
The residue - Inside the mass, if made less dense with carbon disulfide, some objects can be found: human vertebrae and 2 black rocks.
* Researchers had a hard time recognizing and explaining the vertebrae (3 or 4) inside the goo (victims - more than one).
*The rocks are made of basalt magma. Further testing revealed them being over four billion years old, making them older than most known Earth rocks. They are "mare" type lunar rocks from the dark side of the moon. So far meteorites... but, beating all odds, both oriented themselves during their entry, meaning that they stabilized during their flight instead of tumbled randomly. We can tell this by the clear flow lines visible and a characteristic called a lip-over rim on the trailing edge of the meteorite.
Additionally, cosmogenic radionuclide and noble gas concentration tests, revealed the ejection of the rocks being 1.5 and 2 million years ago plus or minus 200 thousand years. (One stabilized flight meteorite is very rare. Two, being ejected thousands of years apart, different ages, floating for a different period of time in space, stabilized flight entry and falling in the same place is nearly impossible).
Game Effects
Treat the noxious gases as exposure to any other poison. It will start as a POT 5 (Burning eyes and throat), increase to a POT 10 (burning of skin) and reach a peak with POT 15 (possible lethal poisening).
The sight of a wailing and thrashing dissolving Hummer in it's death-throes will cost a 0/1d2 SAN loss.