Here we have a set of barrier-experiments that I only got around to answering in-game, rather than online. To catch up with that oversight we have…
1) Scrolls of containment: Each of these scrolls are designed to open into a circle that forms a barrier powered by a type of spirit. using advanced shape-memory materials these unfold fast and smoothly, while being able to store in a container smaller than a grenade. (has a pin for amusement value and to insure it does not open at inconvenient times.) These have loops prepared to attach a handle to carry off the spirit for more secure containment.
This will work just fine, although it’s fairly difficult to catch a spirit this way: they’re fairly fast for the most part, and the unfolding process often provides a bit of warning.
2a) Anti-Spirit Rounds: These normal rounds are inscribed with a small circle barrier attuned to a specific spirit and allow the bullet to damage spirits. Multiple circles can be inscribed into a single round, but space is limited and so are available known spirit interacting barrier types.
2b) Spirit Slayer Shuriken: This shuriken has several circles inscribed in it. When thrown into a spirit that matches any of the types that the barriers were designed to activate off of, it activates allowing for effective ranged attacks on the spirit.
2c) Spirit Scale Armor: This armor is either designed for a specific spirit type or made generic by installing a series of moving pins to form the symbols it uses so that it can adjust to one spirit type at a time. (these can also run off of spells, but this is too unlikely to be useful.) Each “scale” is a disk or ring that has the symbols for a barrier attuned to a spirit. The circles activate when the spirit come into range and either stops the spirit, injures it, or just pushes back.
These all suffer from the same problem: the power source for a circle needs to be inside the circle – and a tiny fragment of a spirit usually isn’t an effective power source. Even if the resonance starts to build, the forming barrier will be weak and will collapse again since it’s blocking out it’s own power source. Throwing little circles at spirits is irritating, and sometimes painful, but it’s rarely that useful as a way to do damage. On the other hand, as a way to harass a spirit, it’s pretty good; a squad of normal people firing circles could build up some fairly substantial penalties for a targeted spirit.
3) Spirit-Slayer Axe: This axe is inscribed with several barriers along its circular blade. The center of the axe contains a toroidal barrier containing one line for each type of known spirit type and has a angle that produces a barrier twice the size of the toroid. This axe does not actually cut spirits with the blade, but rather the barrier that forms once the blade is inside them. It also functions as a normal axe. The toroidal barrier is designed to interact with spirits you hit with the side of the blade and is mostly just for completeness. This works for several weapons, but the axe lends itself to it fairly better.
This would work considerably better if you used a circle attuned to watchers and simply sent a watcher into it to power it. A similar device could provide some magical “armor” simply by using a larger-radius circle.
4) Spirit confetti: Using the principal that magic does not like to travel through magic, these slips of paper each have a symbol that resonates with a different spirit on them. They are tossed into the air and stick to, on, or above spirits. These each have a radio tracking frequency and color that is specific to the spirit. (the radio tracking is extra and optional.) Dumping a load of these will temporarily render a spirit visible (hopefully) and traceable by sensors.
Unfortunately, as noted in a somewhat more elaborate experiment, while these will resonate while within or near the spirit, they don’t stick to it or exert forces on it. They’ll fall right through. There is an odd possibility here though: if you throw a lot of symbols at a spirit and look for which ones resonate, you might be able to tell something about the spirit and the tradition of the magician who summoned it – or even get some information about the true name of a free spirit – by noting which symbols resonate.
5) Spirit Sweeper Drone: This drone is equipped with a hoop that can catch spirits and tow them away. Variants include rotor-drones coated with circles to make spirit resistant armor as per spirit scale armor, but on the blades this can make them particularly nasty.
The spirit-catching hoops will work, subject to the usual limitations of spirit-powered circles. Putting spirit-powered circles on the rotor blades is EXTREMELY irritating to spirits, and might even be moderately damaging: it’s the number of passes; one pass with sandpaper is annoying, fifty can do some damage.
6) Spirit Lasso: This chain with an adjustable loop can change the fine features of its surface when connected with a deck. With included program it can run through a sequence of shrinking circle barriers as it contains a spirit (or one barrier with continuously shrinking font size). Servos and springs in the chain keep it circular and the advanced robot that joins the end with the start of the loop runs along a track and keeps the symbols perfectly aligned.
This doesn’t really work properly; ultimately to change the size of a barrier, it must break and reform, just like changing the frequency at which a resonant chamber is being driven. Now, this can be made very fast – but it’s like the flicker of a florescent light; just not as strong on the average as a steady glow. Worse, since a barrier takes a detectable fraction of a second to form, it loses even more average power.
7) Spirit enhanced tank (or boat, plane, submarine…): This overly large and slightly strangely shaped tank contains a high voltage generator, a toroidal barrier generator attuned to a elemental, a quickened lightning to mana spell, and a elemental of appropriate type for the barrier on long term service using its movement power enhancing the tank (or…). these are designed to be the maximum size to fit the entire tank inside the spherical confines of the barrier so that magic cannot get to the tank without getting through the barrier first.
These can equip a rail gun rather cheaply (sadly these will be limited to smaller caliber weapons, but they are mostly there to fire special reinforced toroid designed to create a toroidal barrier inside a spirit target). Alternate power sources include captured spirits (using a regular circle outside of the toroid so that if it leaves one is is still trapped by the other), employed mages, physical adepts, or any other magic user that has a known barrier language. Elementals are suggested because one mage can summon several, they can enhance the tank on their own, and they are disposable.
Most of these notions were covered under the Flying Saucer research, so I’ll just refer you there (about halfway down the page).
8) Inflatable Toroid Barriers: These inflatable rings come in several variations for several popular spells and spirit types and are the perfect defence against astral threats from spells to spirits to dual natured menaces for the magically talented person on the go. Simply buy one you are capable of activating, carry it with you, inflate with the instant compressed air cartridge when you see danger coming, and activate it. For the truely security concious, you can buy a spirit’s services to power it for you and keep watch for incoming astral threats even if you have no magical talents at all. We have several levels of value and quality, from the inlaid oricalcum chain over natural rubber and kevlar reinforcement to the simple print on plastic in your choice of colors.
This will work, although it gives me some odd notions about the return of hula-hoops and – for the fashionably-astrally-warded sorceress on the go – the hoop skirt.