Minecraft riddles

Cave?

Spider?

No

Diamond? Because a lot of the time there's lava nearby.

At the START

Hint:

I could be your friend, if you could find me

Wolf?>

at the start of the game? good luck getting bones

Hint:

However, it could not be, cuz you have to kill me to survive

ender dragon... all other mobs are run-away-able

yeah... think again. I mean cmon. Can you find the stronghold, go to the end, and beat the ender dragon with your stone sword and no armor? good luck

Pigs or chickens or cows or what?

You have to kill them for meat and later you feel like killing any cow you see?

wrong, but close. VERY close

sheep then? 

YES!

Oh...

A very perplex item i am

containing items countless times more size and mass than me

Even after being destroyed and continually struck

I keep every single one, not even a scratch

Anvil?

Sorry, couldn't resist.

Shulker Box!