Here is the full list of all 46 The Lord of the Rings: War in the North achievements worth 1,000 gamerscore.
Slay one enemy together with 2 other players.
Unlock every active-cast ability in one character’s skill tree.
Create 15 potions in a single playthrough.
Kill 4 enemies simultaneously.
Complete 15 quests in a single playthrough.
Defeat Agandaûr without the aid of Beleram.
Defeat Sauron's Lieutenant Agandaûr.
Achieve level 20.
Amass 25,000 coins.
Help weather the siege of Nordinbad.
Meet a dragon and survive.
Slay Saenathra.
Kill 50 enemies with headshots in a single playthrough.
Free the elf from his captors in Mirkwood Marsh.
Defeat the Sorceror Wulfrun.
Help destroy the citadel within Mount Gundabad.
Kill 150 enemies with war machines in a single playthrough.
Deal 3000 damage with a single ranged strike.
Kill 600 enemies in a single playthrough.
Slay the wild snow trolls.
Achieve at least 1 rank in a tier 3 skill.
Deal 1500 damage in a single melee strike.
Slay Bargrisar the stone giant.
Locate 5 gilded treasure chests in a single playthrough.
Summon Beleram 10 times in a single playthrough.
Slot an elfstone into an item.
Speak with Frodo in Rivendell.
Learn of the Ring of Power and the plan for its destruction.
Defeat the Barrow Wight Lord.
Achieve level 10.
Discover what happened to the missing Rangers.
Defeat Agandaûr's lieutenant Tharzog.
Perform 3 critical hits within 10 seconds.
Revive a fallen ally.
Kill 200 enemies in a single playthrough.
Join forces with the sons of Elrond.
Help free the Great Eagle Beleram.
Discover 25 secrets in a single playthrough.
While in Hero Mode, perform a streak of 50 hits.
Absorb 25,000 total damage during the course of 1 level.
Equip a complete magical armor set.
For one character unlock every skill that provides a modification to War Cry, Sanctuary or Evasion.
Complete a playthrough on at least Normal difficulty.
Complete a playthrough on Legendary difficulty.
Complete the investigation of the Cult of the Lidless Eye.
Complete a playthrough on Heroic difficulty.