Successfully complete the indicated task to unlock the corresponding trait. Traits level up and give your character greater bonuses. Almost all of them are useful, even into the end-game.
Arcane Strike (+Melee Mod Power): Defeat Totem Father or Ravager.
Bark Skin (+Armor): Talk to the Twisted Tree (Earth) with the Twisted Mask equipped.
Catalyst (+Proc Chance): Defeat Thrall or Canker.
Cold As Ice (+Back Attack Damage): Meet Brabus with another player in your team. Brabus will ask you to kill your friends. Do it to get this trait.
Elder Knowledge: Find the Tape Recorder located beneath Ward 13.
Executioner (+Crit Chance Bonus): Defeat IXILLUS on Crosus.
Exploiter (+Weak Point Damage): Kill 150 enemies with weak point damage.
Glutton (+Consumable Use Speed): Defeat the Unclean One.
Guardian’s Blessing (+Reduced Melee Damage): Unlock the dungeon with the Curio lock, and then weaken the boss to 50% HP. When he retreats, stay and kill the Root.
Handling (+Gun Spread and Recoil Decrease): Obtain 10 ranged weapons.
Keeper’s Blessing (+Elemental Resistance): Enter the Labyrinth.
Kingslayer (+Critical Damage): Defeat the Undying King.
Mind’s Eye (+Ranged Damage Bonus): Defeat the Dreamer/Nightmare.
Mother’s Blessing (+Ranged Damage Defense): Free the Root Mother.
Quick Hands (+Weapon Reload Speed): Defeat Ent or Singe.
Rapid Strike (+Melee Attack Speed): Upgrade any non-boss melee weapon to +20.
Recovery (+Stamina Regen): Defeat Claviger on Rhom.
Revivalist (+Revive Speed): Revive your allies a certain number of times (number unknown).
Scavenger (+Scrap Boost): Give the vendor Reggie the Tarnished Ring, or sell an unknown number of consumables.
Shadow Walker (+Enemy Awareness): Unlock the safehouse in a random Earth Dungeon.
Sleight of Hand (+Weapon Swap Speed): Kill 100 enemies with 10 different guns, for a total of 1,000 kills.
Spirit (+Mod Generation): Unlock a monkey key door in a random Earth Dungeon.
Suspicion (+Friendly Fire Defense): Get knocked down and revived by your teammates 10 times.
Swiftness (+Movement Speed): Play the “Guardian Song” at any bell in Yaesha. Skip the second line.
Teamwork (+Teamwork Range): Join a multiplayer session.
Triage (+Health Regen Effectiveness): On Yaesha, encounter the story events where two tribes of Pan attack. Survive and talk to the NPC after the attack.
Trigger Happy (+Fire Rate Increase): Upgrade any non-boss ranged weapon to +20.
Warrior (+Increase Melee Damage): Complete the random dungeon where you must defend the Liz Twins.
Will To Live (+Wounded Health Increase): Get knocked down and revived in multiplayer a certain numbers of times (number unknown).
World Walker (+Stamina Cost Decrease): Enter Rhom.