There are 15 Trophies that can be collected.

BRONZE

Honor in Death
Fall on the Battleground

Ultimate Vengeance
Use an Ultimate Ability to defeat an Enemy Guardian in any Battlegrounds Match

Rise to the Top
Reach Level 14 in any Battlegrounds Match

Warrior's Mettle
Win with a Warrior-Class Guardian in any Battlegrounds Match

Strike Hard, Strike Fast
Win with a Strike-Class Guardian in any Battlegrounds Match

Defend to the End
Win with a Defender-Class Guardian in any Battlegrounds Match

Enchanted
Win with an Enchanter-Class Guardian in any Battlegrounds Match

Fortified
Win with a Tactician-Class Guardian in any Battlegrounds Match

Renowned
Earn 20 Guardian Kills in any single Battlegrounds Match

(MVG) Most Valuable Guardian
Earn a combined Guardian Kill/Assist Streak of 8 in any Battlegrounds Match

Seasoned
Earn5 Accolades from any single Battlegrounds Match

Collector
Kill or Assist a Guardian from each Class once in any Battlegrounds Match

Capture the Power
Capture 15 Shrines total in any Battlegrounds matches

SILVER

Notches in the Axe
Earn 50 Accolades total in any Battlegrounds matches

GOLD

There And Back Again
Win 25 total Battlegrounds Matches

http://www.ps3trophies.com/forums/playstation-trophy-news/26749-guardians-middle-earth-trophy-list.html