Here is the full list of all 19 Knightfall: Rivals achievements.
Complete the tutorial.
Win 10 total battles in either Casual Battles.
Win 50 total battles in either Casual Battles.
Win 300 total battles in either Casual Battles.
Win 10 total battles in either Ranked Battles.
Win 50 total battles in either Ranked Battles.
Win 300 total battles in either Ranked Battles.
Unlock 20 total cards in your collection.
Unlock 50 total cards in your collection.
Unlock 300 total cards in your collection.
Play the game for 5 days.
Play the game for 30 days.
Play the game for 90 days.
Upgrade your cards 10 times.
Upgrade your cards 50 times.
Upgrade your cards 300 times.
Open 15 total chests.
Open 30 total chests.
Open 100 total chests.