Unlockable Mercenaries Mode Characters:
Unlock the following characters in Mercenaries mode by performing the corresponding tasks:

CHARACTER – HOW TO UNLOCK
Ada – Complete Ada’s Campaign.
Carla – Unlock all other characters’ costumes.
Helena – Complete the Urban Chaos map with a “B” or higher rank.
Piers – Complete the Steel Beast map with a “B” or higher rank.
Secret BSAA Soldier – Unlock all other characters and their costumes.
Sherry – Complete the Mining The Depths map with a “B” or higher rank.

Infinite Wing Shooter ammo:

During Leon’s campaign and you run out of extra ammo but still have a couple remaining in the magazine, aim down the sights with the L trigger and press Y to switch to Leon’s duel-wielding mode. Press Y to switch back again to end up with a full magazine.

Trophies:

Bronze trophies
The Longest Night – Complete the tutorial.
Gone to Hell – Complete Chapter 1 in Leon’s campaign.
Buried Secrets – Complete Chapter 2 in Leon’s campaign.
Get on the Plane – Complete Chapter 3 in Leon’s campaign.
Big Trouble in China – Complete Chapter 4 in Leon’s campaign.
The Trouble with Women – Complete Chapter 5 in Leon’s campaign.
Rescue the Hostages – Complete Chapter 1 in Chris’ campaign.
Tragedy in Europe – Complete Chapter 2 in Chris’ campaign.
After Her! – Complete Chapter 3 in Chris’ campaign.
There’s Always Hope – Complete Chapter 4 in Chris’ campaign.
Duty Calls – Complete Chapter 5 in Chris’ campaign.
Money Talks – Complete Chapter 1 in Jake’s campaign.
A Revolting Development – Complete Chapter 2 in Jake’s campaign.
Let’s Blow This Joint – Complete Chapter 3 in Jake’s campaign.
Still on the Run – Complete Chapter 4 in Jake’s campaign.
See You Around – Complete Chapter 5 in Jake’s campaign.
Green around the Ears – Complete the entire game on Amateur.
Check Out My Dogs – Customize your dog tags.
Titular Achievement – Earn 10 different titles.
One Is Better Than None – Purchase one skill.
Silent Killer – Use a stealth attack to take down five enemies.
Finish What You Start – Perform a coup de gr?ce on ten enemies.
Bob and Weave – Counter an enemy’s attack three times in row.
Down, Not Out – Defeat an enemy while dying, then recover without any help.
Lifesaver – Help or rescue your partner ten times.
Give a Little Push – Knock ten enemies off a high place.
They’re ACTION Figures! – Collect 3 figures.
Stuntman – Defeat 20 enemies with the Hydra using a quick shot.
Bring the Heat – Take down an enemy from 50 meters away with a headshot using the thermal scope.
High Voltage – Defeat ten enemies with a stun rod charge attack.
Zombie Massacre – Defeat 500 zombies.
J’avo Genocide – Defeat 500 J’avo.
I Spy – Complete Chapter 1 in Ada’s campaign.
Counterintelligence – Complete Chapter 2 in Ada’s campaign.
This Takes Me Back – Complete Chapter 3 in Ada’s campaign.
Ada’s Demise – Complete Chapter 4 in Ada’s campaign.
What’s Next? – Complete Chapter 5 in Ada’s campaign.
I Prefer Them Alive – Rescue two female survivors at the cathedral.
Flying Ace – Pilot the VTOL without getting a scratch on it.
Hard Choice – Shoot the helicopter pilot with a Magnum at point-blank range.
Sneaking Around – Get through the aircraft carrier’s bridge area without being noticed.

Silver trophies
Normal Is Good – Complete the entire game on Normal.
Back in My Day – Complete the entire game on Veteran.
Weapons Master – Use all the weapons in the game and kill ten enemies with each of them.
Rising Up – Earn a level-four title.
B.O.W.s Are Ugly – Defeat 100 enemies that have come out of a chrysalid.
Covered in Brass – Earn 150 different medals.
Heirlooms – Collect all the serpent emblems.

Gold trophies
Leave It to the Pro – Complete the entire game on Professional.
Mad Skillz – Max out all the skills that allow you to level up.

Platinum trophy
RESIDENT EVIL 6 Platinum Trophy – Earn all Bronze, Silver, and Gold trophies.