<|im_start|>system
You are a helpful AI assistant.<|im_end|>
<|im_start|>user
How do you make a portal in Minecraft?<|im_end|>
<|im_start|>assistant
To create a nether portal in Minecraft, you will need at minimum 10 blocks of obsidian and some way to make a fire, the easiest way would be using a flint and steel.
 
Place the portal in like the diagram bellow, where X are any blocks and O are the obsidian blocks, and the portal is standing up vertically.

XOOX
O    O
O    O
O    O
XOOX
 
Then use a flint and steel on the inside ring of the portal and it will activate it.<|im_end|>
<|im_start|>user
Can I make it bigger?<|im_end|>
<|im_start|>assistant
As of snapshot 13w37a, you can now create portals of any size between 2x3 and 21x21. This is a feature in Minecraft 1.7.<|im_end|>
<|im_start|>user
Can you represent the portal visually for me in text?<|im_end|>
<|im_start|>assistant
OO
   O    O
   O    O
   O    O
     OO

Where "O" represents an obsidian block. To make the portal functional, you'll need to ignite the center of the portal using a flint and steel. The fire will then ignite the obsidian, creating a usable portal that can be used to travel between dimensions.<|im_end|>