Ravas: I am not assigning HD or damage levels to these so you can adapt them to the level of your party as you see fit.

Pile of Gears

Every lab has a pile of broken or miscast pieces waiting for meltdown. This pile is a cleverly disguised security mechanism powered by a small steam engine. It can assume a number of shapes and can disguise itself as part of any equipment or projects in the lab. It attacks with small steam blasts (which drain 10 percent of its HP for 1 hour), slashes with gears, choking tubes and various and sundry pointy bits (piercing attacks). Any natural 20 hit or piercing attack that does more than 10 HP damage has a chance of piercing its engine, which would then release a cloud of choking steam in the room (save vs. breath weapon or take some grievous burning damage).

Hydraulic Ballista

A ballista on a cart that is powered by adding coal or wood to its boiler and which can be moved or driven by a single person. There is metal shielding in front of the driver’s position with a slit for viewing forward. The ballista reloads itself (there is room for three bolts) and has twice the range of a normal ballista. At short range, it deals double damage. There is a remote firing mechanism connected to the ballista via a tether. There is a 15 percent chance per shot of a catastrophic explosion that should kill nearly any driver in the driver’s seat. There is a 2 percent chance per turn of driving of such an explosion.

Lava Suit

A bulky suit of armor with some soft material around it and a looking-glass helmet is tethered by a four-inch hose to a cart-sized box on wheels. When the boiler in the box is filled and the contraption activated, the box pumps various refrigerants through the hose and the suit. This allows the occupant to withstand conditions of extreme heat and in fact submerge in molten lava for up to ten minutes. Should the suit, hose or contraption be damaged, the heat in the suit would rise to the same as its environment in thirty seconds. There is a five percent this will happen in any minute of use.

Hydraulic Ram

This is a steam-powered siege engine for taking down doors and even walls during siege of a fortress. A long metal rod extends five feet out of the machine and four times the damage of a typical battering ram and ignores most enchantments and other means of reinforcing a wall. It must be recharged for two hours per use and when activated has a thirty percent chance of exploding, dealing d100x2 HP damage to anyone within 100 yards not behind a wall or other strong barrier.

Death’s Pinwheel

A disk on the end of an axle is attached to an engine. When activated, the disk spins and extends 20 cables. On the end of each cable is a spinning circular blade. Anyone passing through the radius of the trap must save or be cut to shreds. Those who save take 1d20 damage. To keep this from being a complete FU trap, there’s a 10 percent chance of malfunction after five minutes and a 10 percent chance of malfunction per victim damaged. This trap runs out of steam after three hours.

Pogocart

A three-seat cabin is perched over a large hydraulic leg. Steam and hydraulic power enable this vehicle to to leap 300 feet vertically and up to 200 feet horizontally every ten seconds. In the cabin is a set of horse reins attached to a contraption with many gears and three spinning gyroscopes. The contraption allows the user to control the speed, altitude and direction of each jump.  The driver must make dexterity checks or lose control. The gyroscopes can correct this 75 percent of the time, in which case the cart travels in a random direction (roll d8 and use 8 points of compass). Otherwise, the whole thing crashes. Did the PC’s notice the seatbelts?

Magic Battery

Wands, rods, rings and other small, charged magic items are placed in a canister. There is a – and a + button on a control panel. When the either button is pushed, the canister begins to spin. Concentric rings are lowered from above until they surround the canister. After about five minutes, the rings are raised and the canister stops rotating. If the – button was pressed, the items are drained of magic charges. The charges are stored in a battery in the machine. If there are charges in the battery already, and the + button was pushed, the charges available were evenly distributed to the items in the canister. If there are no charges and the + button was pushed, nothing happens. If there are no items in the canister and either button was pushed, the contraption still cycles but nothing happens.

There is a 40 percent chance the canister spins two slow or too fast, as this machine has not been maintained well. If that happens, the wand, staff, rod or ring will malfunction, doing something suitably ridiculous such as turning the wielder’s arm into a large daffodil or summon five squirrels. A thief, gnome or specialist might be able to calibrate the canister if she checks the machine for problems. Roll an appropriate skill check. The machine is powered by a small coal-burning boiler.

Clockwork Dancing Troupe

This set of human-sized automatons are connected via pneumatic hoses to a central contraption with a steam engine and a difference engine and a panel with many switches. The switches choreograph the automatons, which will perform a dance that has been programmed into the difference engine. A small steam powered organ uses the exhaust steam from the steam engine to play music according to what is punched into a roll of paper that spins through gears inside the machine.

The automatons have a STR of 20 and conceal weapons inside their bodies, which would be difficult to detect. They can be programmed to kill at certain points in the song or when a certain number of people are in the room. There is a 20 percent chance each time the contraption is activated that it will develop its own intelligence, in which case it might follow programming instructions while it plans. Eventually it will attempt to kill or evade its ‘owner’ and escape. The difficult point is figuring out how to get away with the contraption.