On the map, those entrances to a dungeon level look so innocuous: Hash marks to indicate a stairwell, a stylized ‘H’ for a ladder, a curving arrow for a slide.

But dungeon-delving adventurers should be wary. There’s no better place for a monster to call home than at the doorway to another dungeon level. After all, what monster doesn’t want to be first in line at the buffet?

Even game masters working from published game modules should take note to tweak those adventures by adding a little chomper at these entrances and exits.

Spiral Stairs: Something twisty or twisted for those steps that circle down? A brood of iron cobras might hide itself among the wrought-iron grillwork of the stairs. Don’t trust that ivory railing, it just might be a bone naga.

Grand Staircase: Are those carvings of grotesques or smaller versions of gargoyles about to pounce? Watch your step, it’s not damp stone by a gray ooze.

Ramp: Egyptian- or Greek-themed undergrounds would adorn ramps with mosaics and garish reliefs, perfect places to find an array of caryatid columns, mummies or ravenous beetles.

Slide: Every slide turns into a trash chute eventually, the perfect place for an otyugh to settle in. If fed regularly, a carrion crawler might park itself at the bottom of the slide. Organic trash is fertile ground for molds, fungi or an overdeveloped shambling mound.

Archway: What spider, drider or aranea can resist setting up shop, weaving a web or dangling just out of sight? Golems, a suit of armor or other animated objects might be tasked by some long-dead master with guarding an entryway.

Ladder: Pests, such as swarms of biting insects, stirges or a brood of mischievous pixies are likely to take pot shots at anyone climbing up or down a tall ladder.

Magical portal: The more fantastic the exit, the more powerful its guardian. Many djinni have instructions to defend portals, as do various fiends, such as the kyton or the erinyes. Nymphs and dryads can fill that role in certain situations, as do good aligned celestials such as archons.

Those are some of my favorites. What dungeon dwellers do you use to guard entrances and why? Please share them in the comments section.