It occured once that Malazdras, a Sorcerghul who was out on a long slave/sacrificial victim procuring trip, returned, and found his home fortress in a strange frenzy around boring little iron spikes. His master has created a new monster from them, and all his colleagues were busy hammering their own little inventions. Clearly those little rusty things became wildly popular while he was gone, and the competitors were only a claw away from presenting what they made!
But Malazdras wasn’t a ghul of yesterday, and quickly whipped up his own thing.
The Iron Ladder is composed of spikes completely hammered into a wall (stone preferred), then enchanted in a very cost-saving way. Typically, the lower or upper spike can be partly pulled out, and all others follow, forming a ladder or a set of ‘stairs’. Given their size, they are not particularly comfortable to walk on, and are best suited for side entrances and alternative routes. How concealed they will be depends really on their surrounding.
Note that by making only the first or last spike of the ladder functional, prison pits, guarded entrances and the like can be easily created.
A standard addition is the sensitivity to the living. Typically around the middle may be one or more spikes that on touch of a living person will cause the ladder to retract back into the wall, causing the people/creatures on it to fall. The opposite option of letting them all fall out instead is rarely used, even if it offers some measure of fun.
The ladder can be pushed back by using the ‘control spikes’. Sometimes is this feature accessible for undead only.
And how did it turn out for Malazdras? Well, on the positive side was the master pleased by the simple creation, and the many applications. On the negative side, he was starting to be slightly annoyed by the whole iron spike thing.
The last rumour was, that a special ritual would conserve him for another hundred years, and make him an unofficial candidate for the position of an apprentice. Unfortunately, Malazdras vanished soon after, imprisoned by some meddling adventurers, or maybe his master decided otherwise.