The article's distinction of Perception and Investigation is well done.
One thing the article sorely needs is an explanation of the logic behind traps. For example, a trap should make sense and be well hidden. This shows up in a couple places...
1. Nonsensical Traps. A good example is the Sleep of Ages trap, which has a 9th level sleep spell trigger when a pressure plate is stepped on. Wait what? A
pressure plate? Why is that needed to trigger a spell effect? Now, if it was sleeping gas – that's a different story, and also presents more ways the PCs could creatively counter it or use it to their advantage.
2. Obvious Traps. A Pit Trap that can be noticed with a Perception check is kind of useless (unless combined with other hazards/monsters). This also encourages a "Perception optimization" practice among players. Instead, look at monsters with the False Appearance trait: Animated Objects, Blights, Cloakers, Darkmantles, Galeb Duhr, Mimics, Shriekers, etc.
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False Appearance.While the galeb duhr remains motionless, it is indistinguishable from a normal boulder.[/SECTION]
Why on earth wouldn't a trap have a similar property if well-designed? Where it gets interesting is what does the trap
appear to be, and how players can learn to recognize that as a pattern of a given dungeon, and how the DM/module writer can get fiendishly creative within that pattern as a guiding/limiting design principle. For example, in a dungeon with galeb duhr, the players might quickly grow paranoid over large boulders they encounter...the entire dungeon design should then play on that "is it a galeb duhr or not?" mentality, maybe including boulders that need to be moved to access certain areas or that can be dropped on enemies, etc.
3. Placing Traps. While the complex traps rules are neat, I feel like there's more foundational stuff missing from the DMG and this UA article about how should a DM use traps? How should they be placed? All editions of D&D have said "Pit Trap", and modern editions have all said something like "DC # Perception check to notice it." Yeah, duh. That tells a DM nothing about how to use such an obvious pit trap – what other elements are needed to make the threat of that pit actually manifest as more than background color. Now if they address #2, then it's all good, you can have just a pit trap, nothing else. If not, however, there needs to be a section on "Encounters with Pit Traps" that says something like...
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Encounters with Pit Traps. When putting a pit trap in a dungeon, consider the inhabitants means of ingress and egress. They should be able to easily bypass the pit trap, and yet also able to easily leverage its presence in their defense. For example, there might be a closing metal grate that can be winch-tightened by monsters in an adjoining room. Or there might be a concealed passage at the base of the pit for monsters to attack through. A gelatinous cube could wait at the bottom. There might even be a wind funnel in the dungeon that the monsters can remove a stone cap from, blasting intruders who successfully cross the pit back into it.
Monsters that force movement often design Pit Traps. This includes many humanoids that will Shove intruders into the pit using spears and polearms, often Helping one another's Shove attempts. Brass dragons, bronze dragons, and minotaurs make frequent use of pit traps in their lairs.[/SECTION]
4. AngryDM's Click Rule. I see one of the things this article does is trying to distinguish the uniqueness of a trap according to its design. One of the things you see in Indiana Jones is "click" and then Indiana realizes he's triggered a trap. However that doesn't mean the trap immediately takes place. I think that idea should be incorporated into triggers. Maybe tripwires are usually instant effect, but pressure plates are delayed effect?
For example, that Sleep of Ages trap triggered by pressure plate? What if the trap triggers only when weight is put on the pressure plate and then removed? What if that was just how pressure plates generally worked in D&D? All of a sudden that trap becomes so much more interesting! From a players' perspective, now they are thinking:
- What heavy stuff do we have or have we seen in this dungeon that we could place on this pressure plate so it doesn't release the trap?
- Can the rogue lift up nearby flagstones to get in and use Investigation to figure out the pressure plate's mechanism of action? Could that be jammed maybe...and would it last long enough for the rogue and trapped PC to get clear?
- What happens if we encounter monsters in the midst of this?
- Does my PC want to stay near a potential hazard to help his/her fellow, or get him/herself clear to safety?
- Once we're clear could we set an ambush for monsters and use a rope/spell/ranged attack to knock the stone we put on the pressure plate off, thus triggering the sleeping gas?
With these principles in mind, here's how I'd redo the simple Pit Trap...
Pit Trap
Simple trap (level 1–4, moderate threat)
This trap consists of a 10-foot deep pit, concealed by a brittle stone worked into the likeness of the surrounding stonework. This type of trap is useful for blocking off the entrance to a monster lair and usually has narrow, safe ledges along its sides.
Trigger. Anyone weighing 50 pounds or more stepping on the brittle stone might fall into the pit.
Effect. The triggering creature must make a DC 10 Dexterity saving throw. On a successful save, the creature feels the stone shifting under their feet and may use a Reaction to respond with an action; if they remain above the pit trap they fall as the brittle stone crumbles away, grasping the edge at the last moment with both free hands (dropping anything they were carrying). On a failed save, the creature falls into the pit and takes 3 (1d6) bludgeoning damage from the fall.
Countermeasures. A dwarf immediately recognizes the different stone used. A DC 10 Wisdom (Perception) check reveals scuffing along the edges of the floor by the walls (where monsters bypass pit & replace brittle stone). A 1-foot wide ledge around the edge of the pit is safe to cross. Placing an object 50 pounds or more on the brittle stone causes it to break, revealing the pit. The brittle stone can also be destroyed (AC 17, hp 5).
Using a Pit Trap. Combine with monsters using Shove or forced movement like minotaurs, as well as hazards or spells forcing movement like
gust of wind. Consider where the pit trap leads to, whether its a simple pit, a lower dungeon level, or a room with murder holes.