There are a number of methods to protect one-self from the rampagings of some conjured creature. Among them are using protection from evil or good spells, there are better methods, however, when one remembers that mere magic does often not affect creatures from the outer planes. A powerful cleric of a deitiy opposing the conjured creature in question can be very helpful, however, many times such clerics oppose the conjurer as much as the conjured. Among the best methods is the use of protective diagrams. While not inherently magical these diagrams have powers transcending the mundane, like a cleric's symbol. This means that creatures resistant to magic can still be held securely within the confines or out of the confines of such a protective diagram. It should be noted that this is true even for the mighty nobles of the lower planes if they can be conjured.
We will first give a list of the currently known protective diagrams and their uses.
There are different methods of inscribing these diagrams and different methods to use them. We will first give their general power: a diagram of the above type, located on the prime material plane, will not allow any creature against which it has power, to affect it directly with its powers, to cross it by any means with any part or to send its power across the nearest lines of the diagram.
Unfortunately there is a twist: there are diagrams which protect against the inside, i.e. they are designed to confine a creature, and those which protect against the outside, i.e. are designed to keep the affected creature out. It is necessary for the drawer of the diagram to define, of which of these two types the diagram to be drawn will be. A diagram can never be bidirectional, thus it is possible even for a creature which would be affected by it, to destroy the protective diagram if the being comes from the wrong side. The sole exception to this is the pentacle which will keep a seal closed, no matter from which side the opener will come. One should also keep in mind, that such diagrams work only on the prime material plane. A confining diagram confines a space with a height of double its diameter or up to the ceiling. The confined creature cannot get any higher than that. Confinement also reduces the resistance of the confining creature against threats, bargains etc. by 5% each day.
The next point in inscribing a diagram is wether it is to be done by hand, i.e. by drawing the lines with chalk or a similar substance, or by engraving them onto some hard surface. While the latter takes considerably longer it has the advantage that such a diagram can be reused. A hand-drawn diagram is but temporary and will have to be redrawn after one use or with the next sunrise, whichever comes earlier.
Furthermore, there are the questions of the time needed to inscribe the diagram, of the complexity of this undertaking, and the way in which such a diagram is activated. For answers to these questions we will regard each diagram as having a ``spell level'' and a ``casting time''. These are given in the following table.
| Diagram | Spell Level | Casting Time |
|---|---|---|
| Pentacle | 1 | 1/2 |
| Magic Protection Circle | 2 | 1 |
| Thaumaturgic Triangle | 3 | 6 |
| Thaumaturgic Circle | 4 | 13 |
| Pentagram | 5 | 20 |
| Magic Circle | 6 | 20 |
| Great Pentragram | 7 | 28 |
The casting time given is the base time in rounds to temporarily draw the diagram, in turns to inscribe it permanently, provided the necessary materials are on hand. These casting times apply, if the diagram is either memorized as a spell. This memorization takes an appropiate slot, yet can be done by any character able to cast any type of spell. Otherwise, as well as for any character not able to cast spells, the proper drawing of such a diagram will take one turn per casting time unit to temporarily draw it, one day per unit to insribe it. There, however, are a number of special and very rare grimoires, e.g. the Demonomicon , the Book of Yesh, the Liber Ivonis, and others, which also enable their owner to draw such a diagram within the normal base time, provided, he or she has the book and peruses it while drawing the diagram. Depending on the place wher one is and the flux of magic there, the presence of such a book or other unique item might also be necessary to activate the diagram. Usually, however, drawing it properly will be sufficient.
Such a book is also needed to properly understand the making of these diagrams. The chance to understand the drawing of a diagram is equal to the chance of understanding a spell of an equal level for a magic-user with the same intelligence as the reader. If the diagram is not understood, it can be drawn only with the book at hand, and then only at the slower speed, i.e. one turn per casting time unit to draw temporarily, one day per such unit for permanent inscription.
There remains the probability of failure to be discussed. While a properly drawn diagram cannot truly fail it is possible that some crucial mistake was done in drawing it and thus its power is less than expected. A hand-drawn diagram will be incorrectly drawn 20% of the time. This chance can be reduced by 1% for each additional turn of drawing the diagram with special pigments costing 1.000 gp per turn and usually not readily available in a dungeon setting. The initial drawing has neglible costs.
A permanent inlaid diagram has an initial cost of 10.000 gp and a failure chance of 10%. This chance is checked the first time the diagram is used. If it fails the diagram will be totally useless and has to be inscribed anew. The chance for failure can be reduced to 0%, if one uses special metals, gems etc. in the inlay. In this case costs are 50.000 gp and the effort takes an additional month of time.
The requirements given are for diagrams confing a space of up to 10' radius. Hand-drawn diagrams cannot be larger than that. Inlaid diagrams can be larger, in this case time and costs go quadratic with the radius of the diagram. Note that even for very large inlaid diagrams the lines are still very fine and thin.
Against spell or other effects of all sorts a temporary diagram has a saving throw of 19, a permanent diagram has that of the material into which it is engraved +1. A diagram will be rendered useless if damaged or if so much as any one object crosses a single line. This can even be a reed or hair. The creature affected by the diagram has, however, no power to put such an object across any line of the diagram directly, it can of course direct its minions to do so as well as using natural forces, e.g. a strong wind which blows a leaf across the diagram. Note that an object that does not touch the surface on which the diagram is inscribed will not render it useless, a high flying bird thus would be of no consequence.
In addition to the basic failure chance of a diagram there is a chance that a conjured creature is too strong for the conjurer to control. This chance is 1% for every point of combined intelligence and hit dice by which the creature exceeds the character's total of intelligence and level. If several creatures try to break through a circle at the same time, all their hit dice are added up and then the highest intelligence is added to determine the total. If several creatures ``defend'' a diagram against failure, only the highest level or hit dice and the highest intelligence are added. This means that a sufficient number of creatures can break through any protective diagram. Such a breakthrough attempt can be tried only once by each creature or combination of them.
Trying to break through a diagram counts as an action for the round in question, defending a diagram does not. The defender, however, must be conscious and facing the creature against which he defends it. In case no-one is defending the diagram the creature wishing to break it gets a single percentage roll against its total of intelligence and hit dice. Success means that it can break the diagram, failure means, it cannot do so.