Velen is the second area you will visit in The Witcher 3: Wild Hunt. There you will find side quests, hidden treasures and Witcher Contracts: here what and how you will face once in the area. Here is a detail The Witcher 3: Wild Hunt Guide to Velen Side Quests, Hidden Treasures and Contracts.
Funeral Pyres
Travel West from Mulbrydale, on the road you will find a Fire Priest. He will give you a quest: he needs you to fire up three bodies for him. Clear some Ghouls from the area, then use Igni on the bodies after you down some oil. During the firing up of the last set of bodies, a bandit will appear and tell you something more about the Priest. When you return, the Priest will ask if you want to take his bribe or not: if you accept, he will give you 60 gold; if you don't, he and his guards will attack you. Beating him you will of course get a bigger loot.
Defender of the faith (Level 6+)
On your way to East of Blackbough, you will be able to talk with a peasant woman. Pick up the statue for her, get the next part and you will have two more statues to fix. On the first shrine you will face a tough monster, while on the second there are only some humans.
Fists of Fury: Velen
Head to the tavern at the Inn At The Crossroads and you'll see a skirmish inside. Talk to the Bookie to enter into a hand-to-hand brawl again Smithy, the Blacksmith. Bet maximum (on next fights, too) since it's pretty easy to win. Following the fight, head far to the South West to Blackbough and join the second fight. Fast travel back to Mulbrydale and head South to the town of Lindenvale to fight Fishgulper. Last up is the Velen Champion, head to Crow's Perch to take him on. Dodge instantly as he will throw a punch as soon as the match starts.
Gwent: Velen Players
Meet the Bloody Baron during the main quest line. After you search the area looking for his relatives, he will get back to his room and there you will be able to try and beat him on Gwent. Winning that match is the first step of the side quest.
Magic Lamp
Accept this from Keira after you deal with the Wild Hunt in the cave with her. Follow her to a blocked door and then use your Witcher sense to interact with it. You will get a riddle that you need to solve. The statues are in order 3, 2, 4 and then 1.
An Invitation from Keira Metz
Complete the quest Hunting a Witch in the main quest line. When you escape out the end of the cave agree to see Keira Metz again and promise to visit. This unlocks this quest. Travel to her house in the far South West town of Midcopse to complete it.
A Towerful of Mice
After completing An Invitation From Keira Metz she'll ask you to visit a tower and use the Magic Lamp to speak to spirits. Accept the quest and travel to the huge island in the middle of the lake, Fyke Isle. Continue to climb the tower until you reach the floor with the bodies. You don't have to use the Magic Lamp on any of the spirits in the tower, except for the one in the Laboratory.
There are multiple outcomes to this quest. If you speak with all the spirits near and inside the tower you can take the bones back to the main spirits husband and she manifests as an enemy and slaughters him. Returning to Keira to finish the quest gets a response similar to “You've lost your touch” suggesting other methods are better.
Another method is to avoid speaking to any of the spirits and go straight to the Laboratory. Tell her you need to look around more and then try to leave the tower. A Pesta will spawn, kill it and then take the boat across the lake to Graham's house. Speak with Graham and take him to the island, fight your way up through the ghosts that spawn back to Anabelle. Return to Keira and receive a more positive response.
A Favor For A Friend
Keira Metz will ask you to investigate the whereabouts of a package she was expecting. Simply head to the objective marker and search the Northern area for the cart tracks. Follow these to the cart and take the package hidden in a small box underneath. Then return to Keira to complete the quest.
For The Advancement of Learning
Follow Keira to the Fyke Isle and enter the tower again. When talking with Keira respond with the possibility that he is only interested in killing. Then she could kill thousands with a weapon followed by go to Kaer Morhen.
Forefathers Eve
After returning to Crow's Perch to talk with Bloody Baron, the Pellar will ask to provide your services at a ceremony.
The Whispering Hillock
A short distance South East of the Orphans of Crookback Bog (South of Downwarren, South East of Lindenvale) you'll come across a mysterious voice. This automatically starts the quest. A Werewolf is nearby and you'll need to kill it.
After you've killed the Werewolf head into the cave and you'll come across a bizarre growth. Ask all of the questions and you'll get to make a choice. Free the being after collecting Raven Feathers, a black horse and bones (all nearby and easy to locate), or refuse to free it. Choosing to perform the ritual and freeing the spirit frees the children but results in Anna's death in the final quest for this line.
Return To Crookback Bog
When you finish the quest line to help the Bloody Baron locate his wife and daughter, he will ask for your assistance to help free Anna from the Crones. Accept the mission and head to Downwarren to begin the quest. The beginning of this quest may differ depending on your choices in The Whispering Hillock quest as the guards spoke of a possessed horse causing havoc. Follow the Bloody Baron and his guards through the swamp until you reach the Crones houses. A Fiend and several monsters will attack. Typical heavy mob tactics work fine here. Use your Thunderbolt potions and QUEN sign to deal large amounts of damage fast, it's an easy fight
Once defeated you'll need to go speak with Johnny. Follow the objective marker to his hiding spot and clear out the nearby enemies. He's not inside so you need to search the area. Johnny is hiding in a small wooden structure to the North East. Next you need to enter the house and search the basement. When you get into the basement there are 4 dolls, you can only pick 1 to free Anna (the one woven with the flower).
Wild at Heart
This is from the board in Mulbrydale, the town near where you spawn in at in Velen. The next part of the quest is in Blackbough. Talk to Neillen in town and ask about his wife. Talk to the neighbors to learn that she was last seen going into the forest. Go to the area on the map and clear out the wolves.
Now you will have a choice to make. You can either lie and gain some coin and end the quest, or you can say you will find Hannah. If you choose to find Hannah you will need to check the corpse near where the Wolves were for more info. After you find the dog corpse you can find a human corpse a little further away and find out your foe is a Werewolf.
Follow the tracks to the tree and examine the tree. I guess Witchers can't climb so you need to check on the ground for a small tuft of fur. Once you get the scent you can follow it to some ripped up clothes. Near the clothes you can see a shack in the distance, go there. Check the book on the floor of the cabin and you will find the Lair on the outside, under the cabin.
In order to fight the Werewolf you will need to wait until night time for him to return. Werewolves are weak to the Agni sign and Grapeshot grenades. After you bring him down to about 30% HP that other woman will rush in and try to stop you. You can either let the Werewolf kill her or spare her and kill the Werewolf.
Missing Brother (Level 33+)
This contract can be obtained through the Notice Board at the Inn At The Crossroads. As with other contracts you can attempt to bargain for a higher fee.
Thou Shalt Not Pass
You get this when you try to pass the Pontar. The easiest way to get one is to either pay or use Axii with a Delusion upgrade. There is a Shady Merchant near the bridge you try to cross over that has one. You can either pay 100 or 50 if you use the Axii skill. Once you have the pass you can go through the fort and move to the next area.
Jenny Othe Woods
You get this contract from the board in Midcorpse. Once you get the quest talk to Ealdorman. You can Haggle for more gold from him for the quest as well. After you finish, talk to the villager that has info and then go to the fields to search for clues. Check the foot prints and then the torn fabric on the ground. After that follow the foot prints to the blood stain to collect the quest knife. After that follow the foot prints up the hill and to the grave. After you read the letter, return to the village and talk to Ealdorman.
After that go to the fire and burn the letter and the dagger. You will need to wait until night time for the Shade to appear. Use Yrden to trap her and deal damaage, if you have Wraith Oil use that as well