There are 50 Trophies that can be collected.

Bronze

Albus Percival Wulfric Brian
Complete "Dark Times"

Off the Beaten Track
Complete "Dumbledore's Army"

Attempt to Resist
Complete "Focus!"

Did Santa Eat That Cake?
Complete "Kreacher Discomforts"

Accordion to Grawp
Complete "A Giant Virtuoso"

He's Back!
Complete "A Veiled Threat"

Phoenix Rising
Complete Year 5

Chair-ismatic
Complete "Out of Retirement"

The Slug Club
Complete "Just Desserts"

Weasleys' Wizard Woes
Complete "A Not So Merry Christmas"

Sectumsempra
Complete "Love Hurts"

A Riddle Revealed
Complete "Felix Felicis"

Dumbledore's Demise
Complete "Horcrux and the Hand"

I am the Half-Blood Prince
Complete Year 6

Cake or Death Eater?
Complete "The Seven Harrys"

A Wise Disguise
Complete "Magic is Might"

Shedding Skin
Complete "In Grave Danger"

Soul Searching
Complete "Sword and Locket"

The Tale of the Three Brothers
Complete "Lovegood's Lunacy"

Here Lies a Free Elf
Complete "DOBBY!"

To Be Continued
Complete Year 7

“That’s Unfortunate”
Complete "The Thief's Downfall"

Undesirable No. 1
Complete "Back to School"

You and Whose Army?
Complete "Burning Bridges"

Wit Beyond Measure…
Complete "Fiendfyre Frenzy"

Kick the Bucket
Complete "Snape's Tears"

Voldemort's Demise
Complete "The Flaw in the Plan"

All Was Well
Complete Year 8

Idling
Stand still with no controller input for 5 minutes

Weasley Does It
Use a Weasley box with every Weasley

O Children
Complete the scene where Hermione and Harry dance in the tent

Witch!
Unlock all witch characters (Single Player Only)

Pyjama Drama
Unlock every pyjama character variant (Single Player Only)

A Dish Best Served Cold
Defeat Bellatrix with Neville (Waiter) in a duel

Not
Defeat 30 Red Caps

Lighten Up
Use the Deluminator

A Sirius Family Issue
Defeat Bellatrix as any Sirius Black character variant in a duel

Silver

Collector's dream
Complete the Bonus Level

Hogwarts has Changed
Visit the Hogwarts Foyer in Year 7

Halfway There
Unlocked on hitting 50% game completion (Single Player Only)

Avid Reader
Use a Quibbler dispenser 25 times

Lessons Learned
Complete all lessons (Single Player Only)

We are the D.A.
Unlock all of the members of Dumbledore's Army (Single Player Only)

What if?
Defeat every Harry freeplay variant as Lord Voldemort

Tall Order
Unlock ALL of the Order of the Phoenix character variants (Single Player Only)

A Minifig's Best Friend
Unlock every character with a pet (Single Player Only)

Dark Times Ahead
Unlock every bad wizard (Single Player Only)

Gold

But… I Am The Chosen One
Complete the game to 100% (Single Player Only)

Knuts and Vaults
Collect 1 billion studs (Single Player Only)

Platinum

10 Points to Gryffindor
Collect all Trophies

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