I'm in the process of making a subclass based around setting traps - think like Fred Jones from Scooby-Doo. The general idea is that you build traps (duh) but you can only build a few specific kinds of traps (called "trapping techniques") that work kind of like the Battle Master's maneuvers, or the Warlock's eldritch invocations. Each trap has a setup time, a list of required materials, etc. As a minor bonus, the subclass would also make nets not be completely useless. I also had the idea that it would be capable of finding and disabling existing traps in the event that the party doesn't have a rogue or someone else who can do that.

What should the base class be? How should it make nets not be completely useless? What sort of traps should it be capable of making, and at what level? How should I make it not completely useless in direct combat?

Rogue might be the best choice for the base class. (It's tempting to say Artificer, but then you've got all the baggage of being a half-caster class, which I feel like might complicate it too much.)

If you did go the Rogue route, an interesting approach might be to allow Sneak Attack damage to be applied to damage-dealing traps in some situations, and/or (for the 2024 Rogue) add new Cunning Strike options that work with traps.

Nets were reworked a little in the 2024 rules such that they're no longer considered a weapon, and instead of having to make a (bizarrely always at disadvantage) attack roll, the target has to roll a Dexterity saving throw to avoid being restrained. Your new subclass could have a feature (or one of the trap techniques) that imposes disadvantage on that saving throw, or possibly increases the DC.

My first thought was Rouge as well, but that is pretty obvious, I quickly hit on Monk.   With all of that time of (self) reflection that can give the monk some sort of bonus as they "thought" about how to make "x" work.   With wisdom and dex the usual high abilities, it might work out.

First version of the subclass created. I don't have any experience creating subclasses for the 2024 rules, but so far so good, though I think the wording could be a bit better in a few places.

The Trapper

All in all, I think I did pretty good. If there are any technical issues, then it's probably my fault because doing this feels like I'm programming the D&D Beyond website itself sometimes and therefore I might miss a few things.

Edit: Oops, forgot to attatch an image to the subclass. Just imagine Fred Jones from Scooby Doo for now.

Edit 2: Improved the wording in a few places.

I think that the subclass would be near useless in a standard party comp but you could balance it out by giving them some trap options for an action. You could probably make the tripwire a one time use but have it as an action of setup time.

Or you could add a construction time for how long it takes to make the trap and have significantly shorter placement times across the board.

This ability seems worrisome:

Goliath Trapper: When you throw a net at a Huge or larger creature, that creature must make a Dexterity saving throw or have the Prone condition until it escapes. While Prone in this way, a creature’s Speed is 0.

Take a tarrasque. They have a +9 to dex saves, and the dc of that save for a level 9 character is probably 17. That means a tarrasque only has a 65% chance of succeeding. How many level 9 rogues do you think you could find in a city? If you have a few dozen, they could softlock a tarrasque for a long while. Also, it flies in the face of all logic that a single net could make a tarrasque fall prone.

Quick mention, if you want a trapper class, there is a homebrew class from Valda's Spire of Secrets (highly recommend using the book, I've bought it, read through it, and allow the use of it in my games. 10 new classes, 72 new subclasses, and so much more, I highly recommend) called the Craftsman who has a subclass called the Trapper. 

Quote from Jurmondur >>

This ability seems worrisome:

Goliath Trapper: When you throw a net at a Huge or larger creature, that creature must make a Dexterity saving throw or have the Prone condition until it escapes. While Prone in this way, a creature’s Speed is 0.

Take a tarrasque. They have a +9 to dex saves, and the dc of that save for a level 9 character is probably 17. That means a tarrasque only has a 65% chance of succeeding. How many level 9 rogues do you think you could find in a city? If you have a few dozen, they could softlock a tarrasque for a long while. Also, it flies in the face of all logic that a single net could make a tarrasque fall prone.

When you inevitably make your own version of this subclass, you can exclude this ability if you want. I included this ability because the idea of a player shutting down big bosses so that the other players can deal with the ads in relative safety sounds awesome to me as a DM, because it means that the players are actually strategizing for once. I get that most people don't like metagaming, but strategizing and metagaming are not the same thing and I feel extremely irritated when the party doesn't strategize or the DM doesn't allow mid-battle strategizing because "that would be metagaming."
But that's a completely different conversation. Anyway, have fun softlocking tarrasques!

Quote from royalsupsi >>

Or you could add a construction time for how long it takes to make the trap and have significantly shorter placement times across the board.

 The construction and placement times are all wrapped together nicely in the "setup time" section.

Quote from royalsupsi >>

I think that the subclass would be near useless in a standard party comp but you could balance it out by giving them some trap options for an action. You could probably make the tripwire a one time use but have it as an action of setup time.

 Yeah, the tripwire might seem useless in a normal comp, but I have completely exhausted any ideas I have for other trapping techniques, so if you come up with some ideas, let me know. I made this thread for a reason.

Quote from IMPLAYS >>

Quick mention, if you want a trapper class, there is a homebrew class from Valda's Spire of Secrets (highly recommend using the book, I've bought it, read through it, and allow the use of it in my games. 10 new classes, 72 new subclasses, and so much more, I highly recommend) called the Craftsman who has a subclass called the Trapper. 

 How much does the book cost? Actually, scratch that, I'll look it up later. But thanks for the recommendation.

I think it unlikely that this particular scenario would ever come up. If it did the DM should be more then capable to say "No".

Quote from AmberAundguard >>

Quote from Jurmondur >>

This ability seems worrisome:

Goliath Trapper: When you throw a net at a Huge or larger creature, that creature must make a Dexterity saving throw or have the Prone condition until it escapes. While Prone in this way, a creature’s Speed is 0.

Take a tarrasque. They have a +9 to dex saves, and the dc of that save for a level 9 character is probably 17. That means a tarrasque only has a 65% chance of succeeding. How many level 9 rogues do you think you could find in a city? If you have a few dozen, they could softlock a tarrasque for a long while. Also, it flies in the face of all logic that a single net could make a tarrasque fall prone.

 

I think it unlikely that this particular scenario would ever come up. If it did the DM should be more then capable to say "No".

(quotes are being weird, don't know why)

Sure the DM could say no... to the basic use of a subclass ability. Also, that doesn't change the fact that it makes zero sense for a net to knock down a tarrasque.

That is what I am saying teh DM could say no to. They could just rule it non-applicable in that specific scenario.

If we ever get Part 2 of Heliana's, the Trapper Ranger fits this perfectly.

Quote from AmberAundguard >>

That is what I am saying teh DM could say no to. They could just rule it non-applicable in that specific scenario.

Do you have a scenario in mind where the ability would make sense? It literally only works on huge or larger creatures. (as a rule of thumb, a huge creature will weigh about 9 times as much as a medium one)

Quote from Jurmondur >>

Quote from AmberAundguard >>

That is what I am saying teh DM could say no to. They could just rule it non-applicable in that specific scenario.

Do you have a scenario in mind where the ability would make sense? It literally only works on huge or larger creatures. (as a rule of thumb, a huge creature will weigh about 9 times as much as a medium one)

 The scenario I had in mind while making this ability was that while you might not be able to completely restrain a huge or larger creature with a net, you can use it to disable their methods of moving around (legs, wings, etc).

Also, it's D&D. The most famous example of trying to apply real-world logic to D&D (that I know of) was the peasent railgun, and we all know how that turned out...