The game mode unlocks on Stage 8. When you join the Arena, you are assigned to a group, based on the highest Stage you have reached.

It consists of 9 holes, and you have two shots in each game. The goal is to make an Albatross - hole the ball in two shots. As long as no one successfully makes an Albatross, the player can challenge the Hole. The event is in real-time, and if no one made an Albatross on a hole, the winner is the player who got the closest to it. 

How many badges can I earn in Arena? 

The number of badges depends on how close to the pin your ball lands after your second shot.
<100 yards ➡️ 1 badge
<10 yards ➡️ 3 badges

<5 yards ➡️ 5 badges
Albatross ➡️ 10 badges
 
You'll also receive Wolf badges for holding holes when the Arena ends. Check out 🐺 How can I get the Wolf Club?