Tier 1 perks are the first set of perks a user can choose. This group is blue. There are five different perks: Marathon, Sleight of Hand, Scavenger, Bling, and One Man Army. Place your mouse over each icon to see the Pro version of it.

Marathon

The Marathon Perk
Marathon is a new perk that gives the user an inifite sprint duration. In short, it allows the user to keep running without having to stop and walk.
Marathon Pro is unlocked once the user has ran twenty-six miles. Marathon Pro allows you to climb ladders and jump over things twice as fast as normal.

Sleigh of Hand

The Sleigh of Hand Perk
The Sleigh of Hand perk allows the user to reload their weapon super fast. This comes in handy on small maps or with the LMGs like the MG4.
Sleigh of Hand Pro is acheived 120 kills while using the perk. Sleigh of Hand Pro allows you to aim down your sights faster.

Scavenger

The Scavenger Perk
Scavenger is a new perk allows the user to pick up ammo from any player who has lost their life, regardless of what kind of gun they were using. This perk is helpful for people to tend to run out of ammo.
Scavenger Pro is unlocked once a user has resupplied 100 times with the perk. Scavenger Pro allows the user to spawn with max ammo/full magazines.

Bling

The Bling Perk
Bling is a new perk that allows the user to have two different attachments on their primary gun. There are some restrictions though like you cannot have a thermal sight and a red dot sight on at the same time.
Bling Pro is unlocked when the user gets 200 kills with a gun that has two attachments and be using Bling. Bling Pro allows the user have two attachments on their secondary gun.

One Man Army

The One Man Army Perk
One Man Army is a new perk and lets the user change their class without having to respawn. It will also replace your secondary weapon so you only have one weapon.
One Man Army Pro is unlocked when the user gets 120 kills while using the perk. One Man Army Pro reduces the waiting time by two seconds.