||Burrower - The creature is adept at tunnelling through the ground at its normal Movement rate. This is limited to soil and earth.
Dark Sight - Allows the creature to see normally in the complete absence of light.
Tremorsense - A monster with tremorsense can detect and pinpoint the origin of vibrations within a specific radius, provided that the monster and the source of the vibrations are in contact with the same ground or substance. Tremorsense can't be used to detect flying or incorporeal creatures. Many burrowing creatures, such as ankhegs, have this special sense.
Lurkers in the Earth. The ankheg uses its powerful mandibles to dig winding tunnels deep beneath the ground. When it hunts, an ankheg burrows upward, waiting below the surface until its antennae detect movement from above. Then it bursts from the earth and seizes prey in its mandibles, crushing and grinding while it secretes acidic digestive enzymes. These enzymes help dissolve a victim for easy swallowing, but the ankheg can also squirt acid to take down foes.
Engulfing - The creature has an orifice which can swallow targets whole. The maximum size of an engulfed victim is figured as half the creature’s own SIZ, but may be less than this depending on the creature’s physiology. When engulfed the victim suffers at least one damage roll based on the creature’s bite attack before being swallowed – the time spent chewing depends on the creature and how sensitive its innards are. If still alive a swallowed victim will begin to suffocate, likely dying by asphyxiation before suffering any noticeable damage from stomach acid. Realistically, an engulfed victim lacks the mobility to move inside the digestive tract or the creature is so large that he will die long before he can cut its way out. (M2e p314)
Bane of Field and Forest - Although ankhegs receive a certain portion of their nutrients from the soil through which they burrow, they must supplement their diet with fresh meat. Pastures teeming with grazing livestock and forests rife with game are an ankheg’s prime hunting grounds. Ankhegs are thus the bane of farmers and rangers everywhere.
Earthen Tunnels - As it burrows through earth, the ankheg leaves a narrow, partially collapsed tunnel in its wake. In these tunnels, one might find the remnants of molted ankheg chitin, hatched ankheg eggs, or the grisly remains of ankheg victims, including coins or other treasures scattered during the creature’s attack.
Acid Spray (One use per 1 hr). The ankheg spits acid in a line that is 10m long and 3m wide, provided that it has no creature has been engulfed. Resolve as per Concentrated acid (M2e p104), 1d6 damage for 1d3 rounds, applied to 1d3+3 random locations.