* Add 100% for eoch additional feature.

This is the most common form of scrying device, a crystal sphere of about ½-ft diameter. A magic-user can use the device to see over virtually any distance or into other planes of existence.

The user of a crystal ball must know the subject which is to be viewed. 

Knowledge can be from personal acquaintance, possession of personal belongings, a likeness of the object, or accumulated information. Knowledge is the key to how successful location will be, not distance:

* Unless masked by magic or psionics.

The chance of locating also dictates how long a magic-user will be able to view the subject, both with respect to length of period and frequency:

* Unless masked by magic or psionics.

Viewing beyond the periods or frequencies noted will cause the magic-user to make a saving throw versus magic each round, and failure to make it will permanently lower the character's Intelligence by 1 point and drive him or her insane until healed.

Certain spells cast upon the user of the crystal ball might improve his or her ability. 

They are: comprehend languages, read magic, infravision, tongues.

Two spells can be cast through a crystal ball, with a 5% chance per level of experience of the magic-user of working correctly. 

The spells are: 

— detect magic, 

— detect evil/good.

Certain crystal balls have additional powers. To determine this, consult the table below:

The spell function of the device operates at 10th level.

Only creatures with Intelligence of 12 or better have a chance of noticing the scrying. The base chance is determined by class.

For each factor of Intelligence above 12 the creature has an additional arithmetically ascending cumulative chance beginning at 1%, i.e. 1%, 3%, 6%, 10%, 15%, 21%, at 13, 14, 15, 16, 17, and 18 Intelligence. 

These creatures also have a cumulative chance of 1% per level of experience of detecting scrying. 

Treat monsters as one of above as is most applicable.

Check each round of scrying, and if the percentage or less is rolled, the subject is aware of being watched.

If a spell-user (cleric, druid, magic-user, or illusionist) is being observed, use the DETECTION OF INVISIBILITY table on page 60 rather than the percentages above to determine whether the observation is detected, checking each round.

A dispel magic will cause the crystal ball being used to cease functioning for 1 day. 

The various protections against crystal ball viewing will simply leave the device hazy and non-functioning.

(Note: You may allow scrying devices for clerics and druids; water basins and mirrors are suggested. Have them function as normal crystal balls.)