The Battle System was a part of Vdex that was first announced in September 19th 2010.
The Battle System first allowed Users to imulate a battle between 2 pokemon on Vdex. Orginally, the Default Pokemon shown was a Charizard and a Venusaur.
Later, Version 2.0 was announced on November 10 2010. This allowed players to teach their own pokemon battle moves, and then have them engage in a fight.
The first Steps to begin using the battle system was to purchase Some MooMoo Milks. Then you can talk to the NPC Regirock. He'll Trade you them for some cards. The chances of getting cards like so:
1 milk: 10% chance of getting 1 Blank Card
2 milk: 35% chance of getting 1 or 2 Blank Cards
3 milk: 60% chance of getting 1~3 Blank Cards
4 milk: 85% chance of getting 1~4 Blank Cards
5 milk: 100% chance of getting 1~5 Blank Cards
The chances of getting any given number of cards are the same - so if you give him 2 milk and he gives you something, there's a 50% chance it'll be 1 Blank Card and a 50% chance it'll be 2.
This "milk counter" resets when he gives you one or more cards.Once you've gotten some blank cards, you can talk to a Smeargle named Marie who will ask for your pokemon to model, thus giving you a card based on the pokemon that modeled for her. Once a Pokemon has Modeled for her, it cannot model for her again, unless it was collected through Gacha again.