Levitation and flying allow you to untrap falling rock traps.

Falling rock traps can dump multiple rocks onto you at once, up to (depth/4). Damage is taken for each rock. If a trap would drop 4 or more rocks on you, it may instead drop (rocks/4) boulders on your head instead. Helms should be less effective at reducing damage from falling rocks, and almost useless at reducing damage from falling houlders.

If multiple boulders are dropped, they might be dropped on nearby spaces as well, so that a pathway might end up blocked.

Some falling rock traps (particularly deeper in the dungeon) contain one or more boulders instead of rocks.

Casting stone to flesh upwards while standing on a falling rock trap makes the trap drop its remaining ammo as meatballs instead of rocks (which still fall on your head when you trigger the trap, but do no damage).

Add a level flag for the level being open to the sky or otherwise no ceiling. Effects of this include: falling rock traps do not generate, cursed potions of gain level do not work, scrolls of earth do not work; monsters that normally cling to the ceiling are unable to. Levels that would have this: lots of Quest levels, the Elemental Planes.

You can untrap falling rock traps. Unlike dart and arrow traps, this just dumps all the remaining rocks onto that space all at once with the message “The rocks clatter onto the ground”. If there is a monster on this space, it gets hit repeatedly by each rock.

Falling rock traps are reflavored as thwomps from Mario if you are hallucinating.

Falling rock traps are flavored as unstable ceiling (so that the flavor doesn’t get weird for situations like large open levels) and the message changed accordingly. Alternatively, create a separate unstable ceiling trap for that purpose.

All characters should start with a minimum of 11 HP, so they don’t get one-shot by a falling rock trap on turn 1.