The pronunciation is dependent on the source of the word. Baal/Bhaal is a popular demonic/godlike figure in many mythologies and games.
Heck, the perfect example is how it's said in Diablo 2 (as pointed out by you all) vs how it's pronounced in Baldur's Gate 1/2. Funniest part is that D1/D2 and BG1/BG2 released at very close times to each other.
For the record, historically, 'BALL' is the most common pronunciation, from what I've seen and heard.
There are killable stained glass windows that can spawn in City of the Damned. Health bars and everything. Their name in the game is "An Evil Force".
One of the April Fools jokes that was played by Blizzard North was the Deckard Cain rap. You can still find it quite easily on youtube, but it is official. Really really.
Originally, crafting was going to be centered around monsters dropping body parts. Wings, Horns, Hearts, Brains, etc. It got scrapped and for a while it was like Red vs Blue in the office because people wanted them back in.
The Uber Quest and Act 3 are all that's left of the legacy.
There was originally going to be a 2nd Expansion with at least 1 more class (Cleric) which would focus on AoE heals and Pulsing AoE damage. Think Nova, not Auras.
Weird given the Paladin's skills, but it came straight from David Brevik's mouth.
The highest Reqlvl item you can find in the Blood Moore in Normal is a stack of Choking Gas Potions from a shrine at (I'm fairly sure) Req lvl 16.
Though Exploding Potion shrines are more common, in my experience. (Req Lvl 12)
Bonus tip
When you hit one of those shrines, open your inventory and pick up the potions individually. They're in stacks of 1, but if you sell them all to a vendor and buy them back, they're automatically refilled. Expensive though, at a low level. Works for all throwing potions.
Very useful for mana-hungry or melee-based classes in Act 1.
You cannot turn Khaliem's Will into an Iron Golem.
You CAN imbue Wirt's Leg.
I'm not sure if it still works, but you could up a Wirts Leg and its sprite would change into a unique(like Coldkill) Hatchet.
I think the same thing was/is possible with the Horadric Staff.
You can complete a runeword while wearing the thing you're socketing, and it will stay equipped even if you don't meet the level requirement. It won't provide any benefit, however. Saves inventory space in a pinch, though.
Most often this is used by speedrunners for Stealth armor.
There are Red Claw Vipers in A5 red portal dungeons that shoot Infernos instead of poison. A lot of people don't know that.
CE doesn't gain damage from +% fire damage or mastery. -res does work. +Fire skills also works. (Think Magefist or Leaf, not Sorc tree)
The Travincal Council drops a Horadric Cube if you don't have one on your character or in your stash.
Despite being a very high level item (relative to what I'm about to say) Tal Rasha's set amulet can drop as early as the Tombs of Tal Rasha in A2 Normal.
Snapchip and Frozenstein drop like A4 seal bosses instead of what they should because of a fumbled "fix" for Pindleskin drops that didn't actually work in nerfing him.
Prior to being "fixed", the only enemies in the game immune to Blessed Hammer were the demonic apes in Act 3 Kurast. This is because prior to (1.13???) Blessed Hammer bypassed Undead immunities.
All items that a chest drops are of the same magical quality. IE, They're either ALL rare, magic, or unique. No mix. This means it's possible to get a 6(maybe more) unique item drop all at once from a chest. Highest I ever got was 3 in LK.
If Andariel drops gold, she isn't Quest Bugged.
Occasionally you may come across a waypoint that won't let you activate/click it. Go to town via a townportal and come back, then it will work.
In 1.07 (maybe other patches as well, I'm not sure), crafted items can turn out as unique as well. So, it is techinically possible to craft a 20+ MPK Stone of Jordan. Have fun with that.
Bane Ash is like five levels higher than Andariel in Act 1 Normal. (17 vs 12,I think?)
The radius for CE is not accurate for both its fire and physical damage. One of them is a bit shorter than the other. Not listed, though.
The Summoner and Blood Raven are the Sorcerer and Rogue from Diablo 1.
The Jail in Act 1 has secret treasure rooms only accessable via clicking on a torch wall to reveal a secret entrance to the room.
There is a day and night cycle in the game, if you stay in it long enough.
While the fire area from a sorceress' Meteor is just one big thing, the fire from an Assassin's meteor is considered as several different patches. Enemies can be damaged by staying in more than one patch at a time. Thus, it works VERY well against big creatures (Act Bosses) and far less so against tiny ones.
The Soulstones are shards of the Worldstone.
Trang'Oul is spelled Trag'Oul in the Sin War books (pre-Diablo 3 books that ARE AMAZING and you should read them)
Marius is in an opium den in the first cinematic.
How did Diablo (and Marius) cross the sea to get to Kurast before you did, if Meshif was the only captain at harbor?
Jamalla and G.... the other guy in Act 4 are the only NPCs without a Talk option.
If you kill all but 5 remaining monsters in the Den of Evil, prompting the quest, but then a Shaman revives more enemies, your Quest will say 666 enemies left.
There was an easter egG (OR BUG, it's debated) in earlier patches that resulted in having your entire map filled with monsters (completely). It was patched out.
Almost every area in the game will ALWAYS spawn at least one ranged enemy. Because of this, ranged enemies are often more likely to spawn than melee enemies.
If I'm not mistaken, every area only has 3 or 4 monster types at once.
The Ancients actually spawn with items equipped. Thus the large variance in difficulty.
The Sorceress and Druid are the only classes without a Magic damage skill.
Every class except for the Barbarian has a fire skill.
The Barbarian and Druid do not have lightning skills.
The Barbarian is also the only class without a Cold skill.
(For the above, I count Skeleton Mages as Light/Cold skills for the Necro. Otherwise he would be included)
If you step on a critter in the game, you will squish it.
Perspective mode is meant to simulate 3D graphics.
Anya has a crush on Lazurk. Those Shoulders.... mmm... (her words, not mine!)
Cain used to be by the waypoint in Act 5. Now he isn't because we must all suffer for our sins.
Some items that drop in Singleplayer and Ladder do not drop at all on Nonladder.
The rarest item in the game is whatever one you're looking for.
(Also minor mana potions from Hell Baal... I think)
The reason Duriel drops TP scrolls is because people used to get stuck in his chamber. Really really.
De Seis used to steal potions from your belt and then destroy your game files because why not
You don't have to click so much. Hold down the mouse button.
Hiring Act 3 mercs is free if you complete the Gidbin quest.
Every monster, NPC, and Character class has a backstory/bit of lore attached to it that you can find at the Arreat Summit along with their actual damage/resists/AR/etc (for monsters). That's right; there's more than just items there!
Gossip and Quest Talk options change between quests, but also the phase of the quest you are in. There are some real hidden gems that are easy to miss if you plow through the story.
Wirts Leg is a wooden peg, not a bone.
The Blunderbores (big hairy demons with giant clubs) do not actually wield clubs- they are beating you to death with corpses wrapped in chains.
The Zealots in A3 will run away from you after killing the council and opening the way to Mephisto. Forever.
Duriel and Andariel are brother and sister as well as Mephisto's grandchildren.
Lower/Bazzar/Upper Kurast are labeled as Slums/Suburbs/...and I forget the last one. Suffice to say that the Lower/Upper refers to class as well as location.
.... and that's it. That's all I got. I've been wracking my brain over this for about an hour trying to list everything that might be of interest.
My guess is that most will learn at least one thing from this. If you knew it all, let me know and shoot back with your best!
Enjoy your time in Sanctuary, everyone
EDIT: Just want to say that this is all accurate to the best of my knowledge based on experience/forum posts/interviews/wikis/etc. If there is any misinformation or something I didn't get right, PLEASE do correct me and I'll edit the post!