About to run a campaign set entirely in the Feywild. Have used lots of Witchlight for reference, and I've got mostly everything set up. But if the party is just venturing through a magical Feywild forest, nothing too special, what encounters can I throw at them? I know Witchlight has some good random encounters, but they're a bit long and complicated. I'm mainly looking for things set in a Feywild forest and Feywild tundra.

Here are some that I've come up with so far (I still need about 30 more, I'm doing a d100 table):

• Hidden amongst the trees is a magical hot spring, protected by a wise treant.
• A harengon is tending to his orchard. He is willing to sell his fruit for 1cp each.
• A dozen pixies are fluttering through a garden of toadstools, watering the plants.
• A market stall. Standing behind it is a goblin vendor, selling cookies for 1cp each.

The encounters should not last an entire session. Ideas?

One I've used before (not in the feywild but it should fit) was a pair of Faerie Dragon tricksters. 

They used dancing lights and minor illusion to create a glowing figure that beckons the party into the woods, calling for help. This leads them to a group of goblins (or whatever equivalent) which are hostile. after the fight, the faerie dragons swoop in to claim a shiny spoon they saw on the goblins, and which they used the party to get.

Other thoughts...

• An upside down pool which is nestled in the foliage above. Looking up, they see themselves reflected, looking just as confused - and one of their reflections waves. if they touch the pool, it drops.
• a tree which drops huge sycamore-like seeds, which are razor sharp.
• a huge ground-based flower with an organic sign that says "tavern" hanging above a gap in the petals. Entering the flower, there is a pool of beer-like nectar in the middle. The adventurers get covered in pollen as they enter. The flower is entirely natural - not person made. Adventurers are their pollinators.
• Grass which responds to magic, changing colour depending on what spells are cast near it. Base a magic-based fight in a field of this and have coloured crayons to hand for the battlemap! (or use a virtual one to colour it in, you could prepare transparent coloured circles and the like to change the battlemap as the fight progresses!)
• a boulder that runs away. It stays 30ft. from them at all times, and if surrounded, just stops. It's just a boulder.
• A rock carved to look like one of the party. It appears to be ancient.
• a forest which grows overnight. If someone is on watch, then it grows behind them. When they look, the area behind them also grows. Otherwise does not change geography.
• a bush of faintly glowing berries. The berries cause anyone who eats them to make a loud "crack!" noise if they take bludgeoning damage in the next 8 hours, and to shed dim light in a 10ft radius for 1 hour after they crack.

I like the giant tavern flower! These are cool. How come the boulder moves? Is it secretly hollow and something is moving inside of it?

Quote from GameMasterTheo >>

I like the giant tavern flower! These are cool. How come the boulder moves? Is it secretly hollow and something is moving inside of it?

 (1) That's up to you to decide. (2) It doesn't really need any explanation - this is the Feywild.

Researching ancient mythology and folklore about faeries can give you a lot of great ideas.

• A ring of mushrooms. Have the adventurers roll a perception check to see if they notice it, on a fail, they don't and stumble into it and start dancing uncontrollably. The ring is about 30 ft wide and the dancer dances in the center. Anyone that sets foot on the grass begins dancing too. If the characters damage the mushroom ring, the magic is broken and a couple fey creatures attack.
• A unicorn whose horn is stuck in a large tree. The adventurers could do a series of strength checks to free it, and the unicorn may ask them to go slay a lion that tricked it into trapping itself in the tree.
• The adventurers walk by a tree and it suddenly transforms into an ogre. The Ogre attacks them and would like to eat them, and the ogre has the ability to shapeshift into a tree.
• If the players try to take a short rest at the base of a tree, the tree will try to pull them under it, crushing and suffocating them. The tree could be appeased by a song and may provide fruit to anyone who plays for it. 
• A tree with delicious looking apples, but the tree is more real than anything they have ever seen. The apples can barely be lifted by them, trying to eat one might make them take psychic, force, or radiant damage. The characters can do nothing to harm the tree. The leaves and apples would crush them (dexterity checks to avoid them or take bludgeoning damage on a fail) and the characters wouldn't be able to snap a single twig of its branches. It could even be in a sphere of reality where even the grass doesn't bend underneath their feet and is sharp like shattered glass. If a birdnest is in the tree, then the baby bird's cheeping could be so forceful it causes thunder damage, and if the mama bird flies by then her wing beats could create a powerful gale that would blow the characters away.
• A harengon, a mad halfling hatsmith, and a doormouse (and maybe additional NPCs important to the story) have all set up a tea party ([Tooltip Not Found]) and can provide weird, confusing, yet useful information. 

A flail snail with a wizened woman (secretly a hag) that has a small shack built on the back of it and offers bizarre magic items for even more bizarre payments.

Do one of the the classic fey non-combat encounters of a fey trying to buy something you don't think you can sell, such as:

• your voice
• memories
• first born child (which will definitely happen)
• the color green

Have them offer something desirable but not too powerful, designed for your campaign

Tasha's has some nice stuff to draw from "Supernatural regions" and "magical phenomenon" sections in Ch4.

Play on the creepy fey stuff, not just the rainbows and unicorns.  Hags are amazing for this.

If you want just a funny  encounter  that your players  will find funny  how about  a talking  animal  that wants to sell your players stuff like a traveling  sales fey?

I already know about Duffinsmertz.

Sweet  👍 Ok how about  party comes across  a displacer beast  by the river those are always  cool or The Fairy queen  Titania might be interesting  she could asked them to do something  for her or How about  Combine the two  have the fairly queen  ask the party to get a mushroom  from the river and have a displacer beast near the mushroom than if players  get the mushroom  and return  it to  the queen  have her give  them  pixie dust or potions  of some kind potion  made from leftover ingredients? 

Then build  on it a few times each time  queen asks the party to do  something  more serious  . Till she  has the party going to  the. Winter  court  for something  big.