The game has 13 missions around all the world. When you complete one mission you will be able to choose between four perks. These perks are:
1.LIFE:Well you know what life is, it is HP of you. If you choose life your life will improve.
2.ACCURACY:Accuracy means attack damage of you. If you choose accuracy, your attack damage will improve.
3.EVASION:Evasion is the defence. It is the shield of you. When you choose Evasion, you will be able to absorb more damage.
4.INTEL:Well the intel is the enchantment of your accuracy and evasion for %25. You know what they are as i told you.

Well as i said in the first part, you have 13 missions all around the world. But the problem is, agents can go to the same mission. When they do that, they will have to fight. Rule is simple strong one always wins. So choose your mission point wisely.

When you start the game make sure you go to a mission just by yourself. Do some mission and improve your agent.
But you can't go to same mission twice. So the world gets narrow and narrow. If you attemp to attack an agent (you must if you want to win) check their health and make sure you improved your strength.

Hope i helped. Take care and have fun!