This spell functions like symbol of death, except that all creatures of 10 HD or less within 60 feet of the symbol of sleep instead fall into a catatonic slumber for 3d6 × 10 minutes. Unlike with the sleep spell, sleeping creatures cannot be awakened by nonmagical means before this time expires.
Unlike symbol of death, symbol of sleep has no hit point limit; once triggered, a symbol of sleep simply remains active for 10 minutes per caster level.
Note: Magic traps such as symbol of sleep are hard to detect and disable. While any character can use Perception to find a symbol, only a character with the trapfinding class feature can use Disable Device to disarm it. The DC in each case is 25 + spell level, or 30 for symbol of sleep.
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SECTION 15