Every week, a new box pops up with 450 players you can get. Each spin will cost you 25.000 GP (or 250 coins) and you will get 3 players (level 30).
This is also the only Agent that can get you Legends (such as Maradona or Roberto Carlos).
All these players will be level 30, Silver Ball or above.
On most weeks (assuming there are no National Team games), you will get a “Players of the Week” box with 11 players that performed well in real life.
There will also be a “Featured Club” (sometimes even more than just 1) with a selection of players (usually 8) that are rated higher than their default Overall Score. Assuming it’s a decent team, most will be Black Balls.
For both, you can only try your luck 3 times and each spin will cost you 100 coins. You will only get 1 player (level 30) per spin. Keep in mind that you can’t use GP for this.
There are 4 Top Agents you can use:
This Agent is helpful if you want to improve a specific area in your team.
All these players will be level 30, Silver Ball or above.
Every Thursday morning (8 AM UTC), a couple of new challenges become available where you can get an Agent if you win the game/cup. This will usually give you a Silver Ball or above, level 1.
From time to time, new legends will become available. The game will leave a daily Agent in your inbox so that you try your luck. You just need to login during a specific period, usually a whole week.
For instance, you could try to spin those agents to get Batistuta, along with other Argentinian players.