Do caves, ruins, dungeons, camps refill with new enemies, bandits or animals? I mean is it truly possible to kill EVERY thing in oblivion and be left in an empty ghost world.

This makes the assumption that you dont use mods and find a way to kill every one and also makes the assumption that quest npc's dont just become unconcious but actually get killed.

Dungeons respawn after three game days if you avoid them during that period.

The following categories of NPCs respawn: Generic baddies (bandits, necromancers, etc), Black Horse Courier Riders, City guards, Legion soldiers. Generally, NPCs with a generic name like 'bandit' or 'guard' respawn and those with a proper name like 'Captain Viera Lerus' do not.

You already mentioned that some NPCs are tagged essential and cannot be killed as well.

All animals and bandits will respawn after a certain period of time. Guards respawn as well.

Edit: Ninja'd, and by a more thorough post :yucky:

Do the dungeons, caves and ruins fill with the same guys as before? or is the world more dynamic? like lets say a cave full of necros gets killed, well what if some skeltons move in or bandits? possible?

No, they don't fill with the exact same enemies as before. Like if one room had a male Nord marauder, female Khajit archer, and female Imperial bandit ringleader, chances are it'll have a totally different line-up of NPCs next time you pass thru. Loot changes, too, every time. :toughninja:

You can even save your game before you get into a certain area, kill & loot them, but then load that previous save and try it over again. There should be different enemies/loot each time. To make this work, you have to have saved in a different area of the dungeon, though.

Yes, the contents of the cell (including the exact nature of the enemies there) is set at the moment you first enter the cell after having not been there for three game days. Note, however, that both enemies and loot are limited by the type of cell it is. Only bandits will spawn in a bandit location, only Necromancers in a Necromancer location, etc. But the race/gender/class and equipment of those occupants will change from one spawning to the next. This is true also of the containers in dungeons: chests in Vampire caves will have a different mix of random stuff than the chests in a Bandit location, etc.

What I am seeing is if its a cave for vampires then the next re spawn will be vampires?

Exactly. And the chests will contain random loot that spawns according to a rule governing vampire chests (generally speaking, as an example, they contain less alchemical equipment and soul gems than Necromancer chests, but more gold.)

I hope Skyrim is WAY more dynamic if I slaughter zombie infested caves with head shots, necros should move in to do experiments, if I slaughter them then maybe bandits move in

From what I understand (and correct me if I'm wrong) Skyrim's dungeons won't respawn as quickly as Oblivion's, which is every 3 days. Skyrim's dungeons will also be "set" the moment you walk into them. In other words, if you enter a cave at Level 3, the next time you step into that cave, it will be set at Level 3, even if you are level 18, but there will be the chance that some sort of boss character(s) could also be in that Level 3 cave.

I'm personally liking this, as it annoyed me how in Oblivion if you went thru a cave which was all imps at Level 3, and later on you went thru the same cave at Level 14 or whatever, it would now have NO imps but would be packed with minotaurs. It annoyed me how at lower levels you'd see no higher level creatures, but at higher levels, all a sudden the game would be packed with these higher level creatures. Where the heck where they all hiding? :rolleyes:

Bottom line; my description above is probably simplified. There will probably be some surprises in store, I'm hoping.

Im really not likeing how people b*tch about level scaling when its the best thing for a game. at level 20 I dont want to have to travel half the world just to fight level 20. I want to be any where, at any time and fight any thing that matches my strength

I dissagree with you and this is why. At level one, when you have no real experiance surviving in the world fighting a wolf should be a desperate strugle. But when I come back, after end the oblivion crisis, a similar wolf should not still be a rediculous fight. But I want it to still be there rather than ime coming back to a plafe thinking " hey, I need a wolf pelt for a certain quest" and going to where I killed the wolf only to find a minitour lord laughing at me.

Also, since fast travel exists, I don't see why travelling across the world for a challenge would be an issue, unless you were going for a roleplay playthrough.

Note:I typed this on my phone, so please try to ignore any glarring spelling errors

Wolves do not scale. They are always a level 1 creature.

I'm in the minority in that I have no problem with level scaling. My character took 400 hours to reach her top level of 20. That suits my playstyle well and does two nice things that relate to level scaling. First, by taking 20 hours on average per level, the world changes so slowly that it does not jar one at all. When new creatures and gear appear, they do so very very gradually at that pace. Secondly, by capping at level 20, there remain loads of lower level things mixed in with higher level. Yes, my character has seen a minotaur lord, but she also sees loads of wolves and mountain lions. Yes, she has seen bandits with glass cuirasses, but they tend to wear blacksmith pants and elven boots along with the cuirass, and their companions may very well be dressed in mixed up mithril or elven. She still sees many foes using less than top of the line equipment. During the 200 hundred hours she has played while capped at level 20, she has seen exactly three daedric bows and one daedric long sword. I would be happy playing this way anyway, so I don't feel as if I am working 'around' some problem in the game. I play on PC and can easily change any aspect of the game I want, but choose not to change level scaling. :foodndrink:

Level Scaling is ok if it's done right, although Goblin Warlords having massive amount of HP's isn't fun at all. I'm not defending what Oblivion did although I'm kinda glad that I can't get glass armor at low levels but then again every enemy has it at level 20+.

Now onto the OP's question, Dungeons respawn every 73 hours with the same type of enemies although there are expections Hrota cave is one of them, Guards also Respawn, and for some random reason Alga also Respawns. Why she respawns I have no idea.

But I think there is a chance that another type of creature will spawn. Example, in a vampire cave, a vampire may be replaced by undead, since they cohabit with each other. And I think everyone has a chance of being spawned as a rat.

Yes there is a chance that a vampire could just be a rat. It's based off of percentages like for example you might have an 87% chance of encountering a vampire at a specific spot and a 13% chance that the enemy at that same spot is a rat/mudcrab.