Here is the full list of all 51 Gwent: The Witcher Card Game trophies - there are 42 bronze, 5 silver, 3 gold and 1 platinum.
Collect 50 unique cards from 1 faction
Play a card from 5 different factions during a match.
Finish a contract with Gaunter (complete an arena run).
Start a round with 10 points on the board.
Have card advantage of 3 cards.
Have 4 artifacts in play at any time.
Win a multiplayer game by 50 or more points.
Play one arena game.
Smash 100 kegs.
Send "GG" 50 times.
Destroy a unit that is Immune.
Mill 50 cards.
Deal a total of 30 damage to units in one multiplayer game.
Fill your opponent's side of the board with row effects.
Obtain at least one leader from each faction.
Resurrect at least 5 cards in a match.
Reach level 15
Control at least 5 cards with the same power.
Transmute a card.
Order 3 units in a single turn.
Win a game with 2 cards remaining in hand.
Boost unit to over a 30 points in a multiplayer game.
Win a multiplayer game without Golden cards in your deck.
Play a maximum number of units into any single row.
Have a winstreak of 3 in any multiplayer game mode.
Win a round and game, after losing by 20 points.
Get a draw in a multiplayer game.
Destroy 3 or more units with single card.
Destroy a Legendary enemy with a Common ally.
Finish 3 online matches
Play one ranked game.
Win a Regular Battle without redrawing any cards.
Win a battle without killing any of the opponent's units.
Win a round with only Order units.
Play a bronze and a gold card in a multiplayer game.
Complete the basic tutorial.
Get all trophies.
Equip a vanity leader skin, an avatar, a border and a title
Reach level 40
Reach Prestige 1.
Reach Rank 20
Own at least 150 premium cards
Play 5 cards in single turn.
Fully deplete your deck.
Have 3 copies of the same card in an arena deck.
Win a game using 15 special cards.
Destroy a unit with Zeal before it's triggered.
Spawn five allies in a single turn.
Use 10 order charges in a single turn.
Destroy a Doomed enemy with a Doomed ally.
Complete an arena run with at least 6 wins.