Looking for some interesting traps and puzzles to add to a dungeon I'm making. Unique encounters are also welcome!

Here's a cool one I used from my last session. The players really liked it! https://www.youtube.com/watch?v=7uqmGeo8OZs&t=601s

One of my favorite puzzles in dnd I got from a meme. Anyway the puzzle is a door to say a dungeon that when the characters get to the door and attempt to open it it doesn't open. Well turns out the door is a sliding door. Really dumb puzzle that took my party about 20 minutes to solve. It might not work if your players are smart but it was a fun little encounter that got a laugh out of them.

Absolutely beautiful my good fellow! I will be sure to use this lmao.

The top bits of advice I've picked up & passed around for traps are:

• traps which just cause damage (EG you walk in and are hit by an arrow) suck. They just cause damage for no real reason. The only decent way to run this is if there is a pattern to work out in the traps (EG any room with rubble lying around has had a trap in the rubble - so see rubble, expect a trap).
• Puzzles which prevent progress don't work. You either end up having to give them clues, or they spend a long time trying to work it out, or they simply never get it. Puzzles which refuse entry until they are completed should be reserved for side chambers with goodies inside; a reward for passing the puzzle, or a shortcut which skips some dangerous rooms.
• Avoid life or death situations - aim for "life or danger". The consequences of failure should be to set the party back, not outright kill them. For example - a room is filling with water, and they are locked in. If they don't get the door opened, don't just drown them - have them flushed out of the room and into a deeper, more dangerous part of the dungeon.
• If it seems easy to you, who wrote it, it's probably difficult. If it seems difficult, it's probably incredibly difficult. I'm running the "you are in a room" challenge in the forum games section (see signature), and the room is one I considered moderately difficult. It's proving a real challenge for the people playing!

Is this a classic-style "ancient dungeon filled with traps and monsters" I take it?

Some interesting encounters, off the top of my head, which are trap-like:

• A bowl containing a transparent ooze with the key to the door at the bottom
• A long corridor, down which they are pursued by a gelatinous cube. The key for the door at the end is inside the cube.
• A flooded corridor, knee deep, containing water weirds
• A room in which there are two groups of enemies fighting, along with several statues of the enemies fighting. In the middle of the room is a large hourglass, which is endlessly pouring and turning, lasting 12 seconds per flip (2 turns). Every time it flips, those fighting turn to stone and those which were stone turn back to flesh. Anyone i nthe room when it flips is turned to or from stone. There is a puzzle to deal with, as well as the enemies and the fact that half the party is turned to stone every 2 rounds!
• A wall which flips; the floor behind you rises to become the new wall, and the wall drops (like a drawbridge) to become the floor, trapping half the party on the other side (the wall, viewed from the side, is a rotating "+"). The wall is activated by placing a torch in a sconce, and it can flip either way - it could drop you down a floor, or move you through the wall. the party might try and get back, only to drop some of their number down a floor, splitting them even further.
• Fake puzzles - I once heard a good one on here of a statue which demands sacrifices to a god in exchange for a gift. Whatever was placed in its mouth disappeared forever, and it always said "your sacrifice is not enough". A religion check will tell them that the god in question is a god of trickery, and it is just a trick to get people to lose their stuff - there was never a reward!

Quote from ThorukDuckSlayer>>

• If it seems easy to you, who wrote it, it's probably difficult. If it seems difficult, it's probably incredibly difficult. I'm running the "you are in a room" challenge in the forum games section (see signature), and the room is one I considered moderately difficult. It's proving a real challenge for the people playing!

would this happen to be the log room?

Quote from plopped123 >>

Quote from ThorukDuckSlayer>>

• If it seems easy to you, who wrote it, it's probably difficult. If it seems difficult, it's probably incredibly difficult. I'm running the "you are in a room" challenge in the forum games section (see signature), and the room is one I considered moderately difficult. It's proving a real challenge for the people playing!

would this happen to be the log room?

 It would indeed!