dont know they should be in the next update.
All hostile mobs spawn on easy difficulty.
Yes, but the Pigmen and Ghasts won't spawn.
Get single player commands then type in spawn silver fish. Make sure it's not on peaceful.
Silverfish were added to add a danger into stumbling upon an Ender room. These rooms house ender portals and they found them to be too simple and easy. So they decided to add these to make the game a bit more harder, and also for survival maps and other player created things.
It does when its not in Peaceful mode i think
1)They are damaged by soulsand 2) Endermen are attracted to them 3) They where originally modelled as purple Silverfish 4) They occasionly spawn when an Enderman teleports, or when you throw an enderpearl
The only way to spawn herobrine in minecraft is to use mods as you cannot spawn him in vanilla minecraft.
If you mean by mob egg-type things, you can't. Only darkness can cause mobs to spawn.
A dungeon in Minecraft can spawn on any level that normal land can spawn on
No, currently in vanilla Minecraft dinosaurs are not in the game. This means there are no spawn eggs for them.
Wolves will sometimes spawn in forests in Minecraft PE 0.9.0 and above.
In creative mode you can spawn a zombie with the egg