Universal Monster Rule

The creature is alive but is healed by negative energy and harmed by positive energy, as if it were an undead creature.

The monster does not breathe, and is immune to effects that require breathing (such as inhaled poison).

This special attack renders the victim immobile.

Plants are immune to all mind-affecting effects, paralysis, poison, polymorph, sleep, and stun.

A creature with this ability can poison those it attacks.

When a creature with this special attack makes a charge, it can make a full attack (including rake attacks if the creature also has the rake ability).

When a creature with this special attack makes a charge, its attack deals extra damage in addition to the normal benefits and hazards of a charge.

A creature with this ability can choose to make a free combat maneuver check with a successful attack.

A creature with the push ability can choose to make a free combat maneuver check with a particular successful attack (often a slam attack).

A creature with this special attack gains extra natural attacks under certain conditions, typically when it grapples its foe.

Heals damage at a fixed rate each round and cannot die while regeneration is active, except from attack forms that bypass it.

If it hits with two or more natural attacks in 1 round, a creature with the rend special attack can cause tremendous damage by latching onto the opponent's body and tearing flesh.

Ignores a fixed amount of damage of the indicated energy type each time it takes damage of that kind.

The creature (which must be of at least Large size) can catch Small, Medium, or Large rocks (or projectiles of similar shape).

This creature is an accomplished rock thrower and has a +1 racial bonus on attack rolls with thrown rocks. Subject: Medium-baseline rock die (default 1d6), scaled for size.

A creature with the scent ability can detect approaching enemies, sniff out hidden foes, and track by sense of smell within 30 feet (60 upwind, 15 downwind).

The creature can see perfectly in darkness of any kind, including that created by deeper darkness.

The creature perfectly imitates certain sounds or specific voices, with a +8 racial bonus on its Bluff check to mimic sounds it has listened to for at least 10 minutes.

Avoids the effects of spells and spell-like abilities unless the caster's level check (1d20 + CL) equals or exceeds the creature's SR.

The creature splits into two identical copies of itself if subject to certain attacks or effects.

A creature with the stench special ability secretes an oily chemical that nearly every other creature finds offensive.

An opponent grappled by the creature cannot speak or cast spells with verbal components.

A creature with the summon ability can summon other specific creatures of its kind much as though casting a summon monster spell, but it usually has only a limited chance of...

If the creature is in sunlight (but not in an area of daylight or similar spells), it cannot attack and is staggered.