CODE VEIN

True ending
Collect all Vestiges before each boss fight and restore all Successors in the memory scenes during a single playthrough to unlock the "Dwellers" ending, which is the true (best) ending in Code Vein. To save the Successors, thoroughly search the areas before their boss fights. There are special memories called Vestiges. You need to find all of the boss's Vestiges before defeating them in battle. Collect all the Vestiges, then give them to the NPC that resembles Io to save the Successor, freeing them from stone. Since you must save every Successor in the game, you need to carefully explore every area before defeating the boss.

Best items to give NPCs
Give the indicated gift to the listed NPC to get the corresponding points towards building your relationship with him or her.
Coco
Best Gifts (+5): Aromatic Herbs, Chocolate Garlic Flakes, Sushi Tacos, Tomato Oden Sandwich
Good Gifts (+3): Blood Bead Candy, Bottled Jam, Fancy Cologne, Organic Soap, Powerful Spices
Davis
Best Gifts (+5): Antique LP Record, Bugarally Doll, Chocolate Garlic Flakes, Classic Camera, Geisha Noodles
Good Gifts (+3): Blood Bead Candy, Boutique Sake, Expensive Cigars, Protein Powder, Pungent Cheese, Tomato Oden Sandwich, Well-worn Tool, Yellowed Book
Eva
Best Gifts (+5): Flower Seeds, Geisha Noodles, Tomato Oden Sandwich
Good Gifts (+3): Antique Coin, Antique LP Record, Blood Bead Candy, Bugarally Doll, Faded Comics, Fancy Cologne, Organic Soap, Spotless Instrument, Undamaged Paint Set
Io
Best Gifts (+5): Curious Novelty, Local Pendant, Tomato Oden Sandwich
Good Gifts (+3): 35mm Reel, Blood Bead Candy, Bugarally Doll, Chocolate Garlic Flakes, Faded Comics, Fancy Cologne, Fragrant Tea, Organic Soap, Sushi Tacos, Yellowed Book
Jack
Best Gifts (+5): Aged Brandy, Bugarally Doll, Sushi Tacos
Good Gifts (+3): 35mm Reel, Antique Coin, Antique LP Record, Blood Bead Candy, Classic Camera, Expensive Cigars, Flower Seeds, Geisha Noodles, Pungent Cheese, Yellowed Book
Louis
Best Gifts (+5): Faded Comics, Tomato Oden Sandwich, Yellowed Book
Good Gifts (+3): Blood Bead Candy, Bottled Jam, Bugarally Doll, Elegant Fountain Pen, Fragrant Tea, Geisha Noodles, Spotless Instrument
Mia
Best Gifts (+5): Aromatic Herbs, Fragrant Tea
Good Gifts (+3): Aged Brandy, Blood Bead Candy, Bottled Jam, Bugarally Doll, Fancy Cologne, Geisha Noodles, Organic Soap, Powerful Spices, Sushi Tacos, Tomato Oden Sandwich
Murasame
Best Gifts (+5): Board Game, Bugarally Doll, Retro Game, Well-worn Tool
Good Gifts (+3): Antique LP Record, Blood Bead Candy, Chocolate Garlic Flakes, Custom Gun Parts, Faded Comics, Fancy Cologne, Geisha Noodles, Organic Soap, Stuffed Toy, Sushi Tacos
Yakumo
Best Gifts (+5): Aged Brandy, Boutique Sake, Bugarally Doll
Good Gifts (+3): 35mm Reel, Antique LP Record, Blood Bead Candy, Board Game, Custom Gun Parts, Faded Comics, Pungent Cheese, Retro Game, Sushi Tacos

Achievements:
Accomplish the indicated achievement to get the corresponding number of Gamerscore points:
Revenant Preeminent (70 points): Unlocked all other achievements.
Gift Gatherer (50 points): Learn 150 Gifts (excluding those learned when acquiring a blood code).
Deep Trailblazer (30 points): Explore every part of the depths.
Miasma Manager (30 points): Activate all mistles.
Together Until Oblivion (30 points): Listen to partner conversations 50 times while exploring.
Proven Devotion (30 points): Receive 30 presents from friends.
Exalted Reputation (30 points): Raise your reputation as a companion to rank 30.
Burning Spirit (30 points): Unlock the ability to inherit 50 Gifts.
A Weapon for Every Season (30 points): Equip every weapon type.
Revenant Requisites (30 points): Equip every Blood Veil type.
Weaver of Wills (30 points): Collect every blood code.
Gifted (30 points): Learn 50 Gifts (excluding those learned when acquiring a blood code).
Ultimate Armament (30 points): Upgrade a weapon to its maximum level.
Unbreakable Veil (30 points): Upgrade a Blood Veil to its maximum level.
Building Trust (15 points): Give a desired valuable to a friend.
Drink Deep (15 points): Successfully use a special drain from a parry, back attack, or launch attack.
Resonant Power (15 points): Execute a Communal Gift.
Mender of Minds (50 points): Restore all Vestiges.

Additionally, there are secret achievements:
Determiner of Fate (50 points): View every ending.
Queen's Knight (15 points): Defeat the Queen's Knight within your memory.
Queen's Knight Reborn (15 points): Defeat the Queen's Knight Reborn in the provisional government outskirts.
Oliver Collins (15 points): Defeat Oliver Collins in the ruined city underground.
Insatiable Despot (15 points): Defeat the Insatiable Despot in the dried-up trenches.
Butterfly of Delirium (15 points): Defeat the Butterfly of Delirium in the ruined city center.
Invading Executioner (15 points): Defeat the Invading Executioner in the Howling Pit.
Successor of the Ribcage (15 points): Defeat the Successor of the Ribcage in the Cathedral of the Sacred Blood.
Successor of the Breath (15 points): Defeat the Successor of the Breath in the Ridge of Frozen Souls.
Gilded Hunter (15 points): Defeat the Gilded Hunter in the Ashen Cavern.
Successor of the Claw (15 points): Defeat the Successor of the Claw in the City of Falling Flame.
Successor of the Throat (15 points): Defeat the Successor of the Throat in the Crown of Sand.
Blade Bearer and Cannoneer (15 points): Defeat the Blade Bearer and Cannoneer in the Crypt Spire.
Skull King (15 points): Defeat the Skull King in the Gaol of the Stagnant Blood.
Louis's Memories (15 points): View Louis's memory echoes.
Yakumo's Memories (15 points): View Yakumo's memory echoes.
Murasame's Memories (15 points): View Murasame's memory echoes.
Coco's Memories (15 points): View Coco's memory echoes.
Davis's Memories (15 points): View Davis's memory echoes.
Mia's Memories (15 points): View Mia's memory echoes.
Io's Memories (30 points): View Io's memory echoes.
Heirs (15 points): View the "Heirs" ending.
To Eternity (15 points): View the "To Eternity" ending.
Dweller in the Dark (15 points): View the "Dweller in the Dark" ending.
Juzo Mido (15 points): Defeat the boss of the Crypt Spire, Juzo Mido.