The battle styles are:
A -Regular 60 Card match.
B -Minature 30 Card match.
C -Ultra 90 card match.
D -30 minute match (AIM only).
E -60 minute match (AIM only).
F -Gym Match.
G -Tournament Match.
Here's what the winner gets for each style:
A -Winner: Free Common Card
B -Winner: Free Common Card
C -Winner: Two Free Common Cards
D -Winner: Free Common Card
E -Winner: Free Uncommon Card
F -Winner: Free Rare Card (+ Prize)
G -Winner: Free Rare Card (+ Prize)
Gym and Tournament are paid on top of the style.
All timed matches are 60 card.