Here is the full list of all 49 Magic Duels achievements.
Win a duel with five or fewer cards in your library
Have a creature enter the battlefield and return a creature to your opponent’s hand on the same turn
Control four creatures with flying
Complete Gideon’s Campaign
In a single duel, have your flying creatures deal 15 damage and be dealt no damage yourself
Starting on your third turn, attack every turn until you win
Reduce your opponent’s life total to 10 or less before your fifth turn
In Jace’s Campaign, win a duel by depleting your opponent’s library
In Liliana’s Campaign, return three creature cards from your graveyard to your hand in a single duel
In Chandra’s Campaign, deal 10 damage to your opponent with instants or sorceries in a single duel
In Nissa’s Campaign, control a creature with total power and toughness 20 or greater
Win 10 Solo Battles
Win 100 Solo Battles
Win 500 Solo Battles
Win 10 Versus Battles
Win 100 Versus Battles
Win 500 Versus Battles
Hit rank 5 in ranked Versus Battles
Hit rank 10 in ranked Versus Battles
Hit rank 15 in ranked Versus Battles
Hit rank 30 in ranked Versus Battles
Hit rank 40 in ranked Versus Battles
Open 10 booster packs
Collect all five Origins Planeswalker cards
Get a mythic rare card
Collect all the mythic rare cards in Magic Duels: Origins
Complete 10 Daily Quests
Complete 100 Daily Quests
Complete 500 Daily Quests
Win a duel with a custom deck
Have Gideon, Battle-Forged deal 12 damage in a single duel
Cast two instants or sorceries from your graveyard in a single duel
Return three creatures from graveyards to the battlefield in a single end step
Deal 12 damage to an opponent with Chandra, Roaring Flame in a single duel
Deal 12 damage to an opponent with lands in a single turn
Put two creature cards from your library into your graveyard in a single duel
Sacrifice a creature owned by an opponent
Deal 10 damage to an opponent in a single duel using creatures he or she owns
Have two lands enter the battlefield in a single turn
Cast a creature spell with converted mana cost 7 or greater by your fourth turn
A creature you control becomes renowned
Deal 10 damage or more to your opponent with renowned creatures in a single turn
Control six Elves
Control 20 Elves
Control five artifacts
Tap or sacrifice five artifacts you control outside of combat in a single turn
Search your library for an enchantment card
Attach four Auras to the same creature
Put three tokens onto the battlefield in the same turn