Mek

Meks are huge metal constructs built by a long-vanished race of insectlike sorcerers, and the name may derive from 'mechanical'. Most copy their makers, with barrel chests and long, double-jointed, barbed limbs, but some take the shape of giants, lizards or other creatures.

A mek has 1d6+10 Hit Dice and senses only motion, so a creature holding perfectly still is invisible to it. The best defense against a wandering one is to stay out of its way and remain frozen for about 1d3+1 rounds while it passes, succeeding at a Dexterity check every round.

Its two fists each deal 5d6+10. A creature hit by both in the same round must save vs. paralyzation; failure means it is flattened and stunned for 1d4-1 rounds, and success still leaves it prone. With an effective Strength of 22, a mek can also seize an enemy on a hit and fling it 1d6x10 feet, for 1d6 damage per 10 feet plus its +10 Strength bonus.

Once per turn it can breathe out a stationary 10-foot-radius sphere of clear, paralyzing gas that lingers for 2d4 rounds even if the mek moves on. Each round inside requires a save vs. breath weapon to avoid 1d3 turns of paralysis.

Most enchantments do nothing to a mek, and poison and mind-affecting attacks fail. Cold spells deal no damage but slow it as the spell. A disintegrate spell destroys a mek that fails its save.

A mek sealed in with a master was 90% likely given a final order to guard a chamber, object or whole level; otherwise it was told to kill anyone who entered. When erosion uncovers a stronghold, a mek that had no master may break free, and with no compulsions or safeguards it wanders, attacking most creatures and leveling buildings. The art of making meks is lost, for now.

A mek sealed inside with a master has a 90% chance that its final command was to guard a chamber, object or entire level, and otherwise it was told to slay anyone entering. When erosion opens a buried stronghold, a mek that had no master at sealing may escape. Lacking any compulsion or safeguard, such wild meks roam the land, attacking most creatures and flattening buildings. How to build one is lost, for now.

Wild meks aside, they barely affect their surroundings. Some scholars suspect a link between meks, iron golems and the crab-shaped submersible apparatus of legend.