Figured I create a topic about all the items, ingredients, potions etc.. that give a permanent boost since I have not seen a single topic that has all of them and this makes it easier than searching for them individually on the forums or searching the .pdf guide(which is where I got the info from, feel free to help since I'm only on act 2 on BD) which gets confusing. Haven't seen another topic like this but if there is then I wasted some time I guess.

Act 1:
Permanent Survival Potion(adds +1 to survival: On the torture Level, after you kill the torture master you'll find a room near it that has a mana and life shrine, its on the chest on that room.

Permanent +60 Life Book: On the Pit level, on the first room you start, leave and keep going to the right passage until you see another room, on it you will see a statue and a bunch of boxes to the left of the statue, move those boxes and you will see a switch, pull it and the statue will move to reveal a secret entrance, you will see a book on an altar, the person who clicks on it gets the bonus life and the book disappears.

Act 2:
Holy water, Ingredient for permanent potion: On the Spider Forest, on the entarnce, go north-east and you'll see a cave, talk to the hermit and he needs get the an amulet. The amuler is in a pit just northeast of your current location, once in the pit travel West and grab the amulet from the chest, your reward will be the Holy Water.

Permanent Intelligence Potion(+6): When you enter the mushroom forest, run south-west and enter the cave, its on the eastern part of it, you'll have to kill or steal it form the lich.

Permanent Mana Boost(+60):In the Cursed Abbey, once you get teleported there by zandalor go up to the first level(you first get teleported to the basement), on the first floor you have to go to the most northern part of the cathedral, its where you'll find the Paladin Leader. To the left of where you meet the leader you'll see a cup(I think it was a cup), the first character who grabs it gets the mana boost.

Act 3:(Alright I'm not this far so anything from here on its from the pdf guide.)

Permanent Survival Potion: On the eastern part of Crystal Forres you'll find a orange crystal, the crystal will ask you to kill 4 demons, kill them and come back to the crystal for the potion.

Permanent Constitution Potion: No idea where or how, but the guide says there is one.

Act 4:

Permanent Intelligence Potion(+6): Join the Philosophy faction.

Permanent Vitality Potion(+60): The summoning level, Permanent , ridle quest, you'll have to push the red button to get to the chest.

Permanent Mana Potion(+60): The summoning level, Permanent , ridle quest, you'll have to push the Blue button to get to the chest.

Permanent Stamina Potion(+25): The summoning level, Permanent , ridle quest, you'll have to push the yellow button to get to the chest.

Permanent Constitution Potion(+1): The summoning level, Permanent , ridle quest, you'll have to push the green button to get to the chest.


Leveling:

Depending on the difficulty you can earn less bonus by spending attributes, for example on easy you get 100 mana for every 5 points into intelligence, on Hardcore you get 75. So it would be smart to start on the easiest difficulty and spend the points there.

On Hardcore you have a 30% chance to get 2 skill points at level up, so at level 10 you would have 22 skill points(you gain a bonus 1 every 5 levels, and when you start the game on easy you start with 2 skill points). The Wisdom skill makes this much easier since it separates the characters experience, so they won't both level at the same time. The bad part is that once you're in the hardcore difficulty you cannot go back and get the bonuses you get on easy.