There is a honeybee statblock in Wilds Beyond the Witchlight. Also a regular spider in the Monster Manual, which could work just as well. Apparently the average spider in the Forgotten Realms is poisonous enough to have a 15% chance of immediately killing an average commoner with a single bite
If your PC has the ability to turn into a fly, then the game has deliberately given them some amazing stealth and scouting capabilities. I say this is working as intended.
How does a DM deal with players who look for these wild ideas?
I think it's fine to think outside of the box and metagame. But does it end up in a slippery slope where it feels like the players just want to outthink every encounter where it's just a rube Goldberg set of plays?
There isn't anything to "deal" with. If you want your players to only give predetermined solutions to problems, you really need to play a different game.
But say by adventure 10, they're still trying to beat the system. It feels exhausting trying to create a story like "A vampire council, but they have anti-magic doors so you can't disguise yourself. And also no rats. And you can't teleport in there. And summoning a devil or warping the castle is forbidden. And..."
If you're not a fan of this type of behaviour, I recommend playing a TTRPG that isn't D&D.
D&D has gotten a bit of an "LULLZRANDOM!!11!!" reputation, possibly because of the content creators needing something whacky to get views, or just because of how mainstream it is. If you need to stand out in a crowd of thousands being extreme, novel, or whacky has the lowest effort for the highest reward.
If everyone at the table finds the game fun, then you are playing correctly. I find this behaviour exhausting and would tell the players that it needs to stop unless someone else wants to GM.
What would examples of alternative TTRPGs be? And what characteristics would they have that would prevent the "LULZRANDOM We're breaking the system" type of gameplay?
I'm thinking maybe crunchier and more in-depth rules ala Pathfinder or GURPS, since the barrier-to-break is much higher due to having to read more, but I'm just guessing as a relative ttrpg novice here haha
Imo this is firm "you can get away with it exactly once" territory. It's clever, so it should be rewarded. But after the once every lord will mysteriously have anti-shape shifting wards.
Personally I think the players coming up with some cool new trick for each encounter sounds pretty good. The problem is when they find one cool new trick that works for everything. Like, casting Create Water in someone's lungs sounds awesome the first time you do it, but you don't want a whole campaign of just that. But even if the players agree that that would be boring, it's hard not to do that without justifying why it wouldn't work, and if it wouldn't work every time, why would it have worked the first time?
Create water doesn't work inside a person because all living things inherently have enough magical ability to resist spells cast on or in their person. Damage dealing spells have to be specifically designed to work on people, or they have to be able to attack someone by applying an external force.
Strategically placed near every door, window, sewer pipe, and vent the DM put an Antimagic Field device.
I especially like to imagine a druid coming in through the sewer as a rat and having his robes get soaked in poo when he gets popped out of wild shape.
Strategically placed near every door, window, sewer pipe, and vent the DM put an Antimagic Field device.
I once played with someone who argued that Diplomacy would never be usable on any important person because, since it requires 1 minute of uninterrupted conversation to use, everyone who is important enough would have a jester or aid or someone they'd hire specifically to interrupt every conversation they were involved in every 9 rounds. Absolutely infuriating person to play with. This anecdote is completely unrelated to this post, but your suggestion just made me remember it again, and it irritated me all over again.
That could make for a fun gimmick(tie it to a roll behind the scenes) for a session, but beyond that, fuck no. Not only would it be an absolute drag timing out each conversation, eventually the party will start working out ways to get around it, be it a graceful zone of silence to the more likely "Gut the loudmouth and use the corpse as a puppet".
Why would anyone want their diplomacy interrupted, even as the one being affected? It's not like diplomacy is some evil spell. A successful diplomacy check means you were able to have small talk, relate, and do all the normal things strangers do to put each other at ease. You don't "defend" against diplomacy!
Imagine trying to agree on a treaty with some jester interrupting every 54 seconds...
Antimagic field is an eighth level spell with one hour concentration duration; an item that has it on 24 hours a day would easily be a legendary item. People underestimate how powerful a spell it is and suggest spamming it everywhere. Having it on every door, window, sewer pipe, and vent would be massive overkill just to spite wildshape.