Your own non-biodegradeable watchdog.

Power: Significant
Cost: At least 4 significant charges.
Effect: This spell creates an animate pile of Styrofoam peanuts, about the size of a medium-sized dog, to patrol a given area and keep it clear of living intruders. The ritual was probably used originally to animate human refuse and offal to serve as a sort of a miniature sludge golem. Whatever. These days, it works just fine with Styrofoam.

You’ll need a large supply of good sized Styrofoam peanuts. Not the made-from-starch kind; long chain polymers only, thank you. Enough to fill a large box. The entire ritual should be done inside, after midnight on a full moon, without allowing the moon’s light to touch the peanuts. Dump the Styrofoam into a large metal container. Each person you wish to be exempt from the sentinel’s prowling needs to add at least a pint (.5L) of blood tapped fresh from the vein while they meditate on a secret they’ve never told anyone before. At least four pints must be added, so it’s best to use multiple people. Once each person has added their blood, start a fire under the container and bring the mixture to a boil. Instead of burning, the peanuts will melt down into a thick sludge. Incidentally, good ventilation is recommended during this step. Better adepts than you have passed out into their own blood and polystyrene to find that the mixture is highly acidic at this point (doing firearm damage if you’re dumb enough to get it on yourself). Keep it boiling until the sun rises, when each person who added their blood should spend a significant charge while they recite the secret they’ve never spoken. If successful, the mixture will quickly boil down to three to five blood red Styrofoam peanuts. Pick one of these up with tongs – they burn like acid too if you don’t – and place it in a pile of plain Styrofoam peanuts. Breathe on the pile to give it life. Voila, your own Styrofoam Sentinel.

A Sentinel protects the building it was created in. Most of the time it looks like a plain pile of peanuts, the blood red core hidden inside. When not lying still in wait, it usually moves like a starfish, perhaps a foot or so a day at most. However, when an organic being other than one of its creators approaches, the Sentinel suddenly oozes as fast as an average man can move and attempts to slither into the victim’s mouth, blocking the airways, filling the lungs, and suffocating him. The Sentinel is fully capable of going up and down stairs, as well crawling on walls and ceilings, and moves with a disconcerting ‘squeaking’ sound. It will attack anything that is not one of its creators, without question. So sorry about your friends and pets, but on the plus side, just one of these can keep a warehouse rat-free. If left alone with a corpse of any kind, it will dissolve all organic matter leaving behind nothing but bones (and fillings, and surgical pins, and loose change…)

Some people say that after feeding, their sentinel seemed to look bigger. But that’s just a rumor.

If attacked by one, your best bet is to plug your nose and mouth and run from the area. Of course, when swarmed by living Styrofoam, most people’s first reaction is to scream. Firearms and hand to hand attacks do zero damage to a Styrofoam Sentinel. However, any peanut that’s scattered more than half a foot (15cm) away from the main pile becomes just another plain piece of trash. This is why they don’t go outside: strong wind or water can scatter them completely. A Dipsomancer’s blast is a surefire way of destroying one as well. And fire is completely inimical to them. If someone’s bearing a torch, a Sentinel will hide.