A direction bug can cling to walls and even ceilings. In effect, a direction bug is treated as constantly being under a nonmagical version of the spell spider climb. This ability doubles the normal +8 racial bonus to Climb checks normally afforded creatures with a climb speed to a +16 racial bonus.
A direction bug has the supernatural ability to innately determine the direction of true north at will. Other creatures can make use of this ability by taking a direction bug and spinning it on its back. The direction bug will use its two antennae (or wings, for a flying direction bug) to stop its spinning. When it does, it always stops with its head pointing north. This ability works on any plane with a definite north, south, east and west (generally found only on planes with objective gravity). Direction bugs spun on other planes will stop with their head pointing in any random direction.
A crystal direction bug has the supernatural ability to innately determine the direction of true north at will. However, it doesn't impart this information as readily as other direction bugs do. When spun on its back, it will always stop with its head pointing towards a cardinal direction. the DM should secretly roll d%. On 1-40 the direction bug points north, 41-60 south, 61-80 east, and 81-100 west. This ability works on any plane with a definite north, south, east and west (generally found only on planes with objective gravity). Direction bugs spun on other planes will stop with their head pointing in any random direction.
By whirling their antennae in a specific way, direction bugs can tunnel through earth at a surprising speed. This acounts for their burrowing speed. A direction bug with only one antennae has its burrowing movement reduced by half. A direction bug without any antennae cannot burrow at all. The burrowing is such that the path created collapses just behind the direction bug, forcing pursuers to dig on their own if they wish to follow.
If a direction bug is set loose on a earth elemental (or other creature made of dirt, sand, soil, etc) at least three size classes larger than it, their natural burrowing causes 1d4 damage (3d8 for a Fellspawn direction bug) each round it attempts to travel inside the elemental. The elemental may make a single Reflex save each round (DC 20) to expel the direction bug and take only half damage.
Spellbane direction bugs constantly emanates a Mind-Affecting field to a distance of 25 feet. Any creature attempting to cast a spell or use a spell-like ability within the keen emanation must make a concentration check (DC 15 + the level of the spell being cast), or else lose the spell. This check is in addition to any other concentration check(s) that may apply (such as the check required for defensive casting or after sustaining damage).
If a creature is in the Aura of multiple direction bugs, they must make a concentration check for each direction bug. However, the DC decreases by 2 for each other Aura the creature has overcome in the current round. (Casting a cantrip with three direction bugs nearby would require concentration checks against DCs 15, 13 and 11.)
A fellspawn direction bug can choose to forgo all other attacks in a round and instead focus a whirling barrage against a single opponent. Treat this as two separate antennae attacks with an additional +2 to the attack and damage rolls.
Creatures damaged by an antenna must make a Fortitude save (DC 12) or be paralyzed for 1d6+2 minutes.
On a successful bite, the direction bug injects a mild venom into the victim's bloodstream that clouds the senses. Treat this as the spell Confusion. Will negates, DC 14.
The Fellspawn direction bug's poison is stronger and gives a -2 penalty to the save.
It's a common superstition that, like a mockingbird or an albatross, no good can come from harming a direction bug. Amberlei used this superstition as a base when he created his monstrous direction bugs. Anyone who catches sight of an fellspawn direction bug must make a Will save (DC 18). If the save is failed, the viewer is suddenly filled with a supernatural dread. If attacked by the direction bug, they will try to flee or cower rather than risk harming it. Those who witness the direction bug paralyzing or killing one of their companions may attempt another saving throw to overcome the effect. Those who make their save are immune to the Aura of that direction bug for 24 hours. This is a Mind-Affecting, Enchantment/Compulsion effect.
It's not an uncommon sight to see peasants or travelers lugging small canvas sacks filled dirt. They're carrying one or more direction bugs, small 3-inch creatures with useful compass-like abilities.
Direction bugs are similar in shape to ladybugs, shaped like an egg spit in half, ovoid in shape and flat along the underside. Sensory organs surround a surprisingly large mouth on its narrower end, called the head. Ten small legs stick out of the underside, plus two larger ones. These larger legs are called antennae and are as long as the rest of the direction bug's body. They connect to the body at a point under and just to the side of the mouth. The body itself is chitinous, creating a turtle-like shell around the direction bug's softer insides.
All direction bugs can eat plain, everyday dirt. Certain types of direction bugs may have preferences for certain types of soil, or other foods entirely, but they are all capable of eating unpolluted dirt, soil, dust, gravel and sand. Direction bugs seem to have no need for air, so are usually kept in canvas bags of their preffered soil. The direction bug will not eat canvas, but consumes about 5 times its weight in soil a day.
It is considered a sin or bad omen to kill or injure a direction bug, as they are harmless to crops and people, cost almost nothing to maintain, and provide a welcome service. Mages that employ spells that consume direction bugs are despised. Most of the spells needing direction bugs, therefore, do not consume the direction bug in their casting.
Direction bugs live for about a year. They are hermaphroditic, having both male and female reproductive organs. Two direction bugs may meet, each donating sperm to the other, which they can hold for up to two months. A direction bug may collect sperm from several other direction bugs before it finally lays eggs, though it usually stops at six. Starting in its second month, and every months thereafter, a direction bug will lay a clutch of 40-60 eggs, usually beneath a large rock, then dump its collected sperm on it, plus some of its own. Assuming they are not eaten before they hatch, the baby direction bugs hatch in a week and immediately start burrowing away, eating and eating until they reach their full size in one month.